diff --git a/Services/Iec61850DataSetSignalInventoryService.cs b/Services/Iec61850DataSetSignalInventoryService.cs
index a4476b3c..705079fa 100644
--- a/Services/Iec61850DataSetSignalInventoryService.cs
+++ b/Services/Iec61850DataSetSignalInventoryService.cs
@@ -26,11 +26,11 @@ public static Iec61850DataSetSignalInventoryMergeResult EnsureMandatorySignals(
     {
         ArgumentNullException.ThrowIfNull(device);
 
-        // Signal Selection is also opened directly from an offline CID/SCD workspace.
-        // In that workflow LiveDiscoveryModel is intentionally null; the SCL design model
-        // is the authoritative inventory and must not be ignored. Prefer the live model
-        // only after a real association/discovery has produced one.
-        var authoritativeModel = device.LiveDiscoveryModel ?? device.SclWorkspace?.DesignModel;
+        // When an SCL workspace is open, its configured DataSet membership remains the
+        // engineering authority across cached/fast reconnects. A partial live discovery
+        // model must not erase FCDA/FCD rows that were proven by the opened CID/SCD. For an
+        // online-only IED with no SCL workspace, live discovery remains the authority.
+        var authoritativeModel = device.SclWorkspace?.DesignModel ?? device.LiveDiscoveryModel;
         if (authoritativeModel is null)
             return EmptyResult();
 
diff --git a/Services/Iec61850StaticDataSetAuthoritySelection.cs b/Services/Iec61850StaticDataSetAuthoritySelection.cs
index 63844047..5296d816 100644
--- a/Services/Iec61850StaticDataSetAuthoritySelection.cs
+++ b/Services/Iec61850StaticDataSetAuthoritySelection.cs
@@ -6,11 +6,17 @@ namespace ArIED61850Tester.Services;
 /// <summary>
 /// Builds the exact Static DataSet selection used by the report-only workflow.
 ///
-/// A DataSetReference on a browsed/runtime alias is not sufficient authority: several
+/// Static report-only mode is RCB-backed by definition. A static DataSet that is not
+/// referenced by an authoritative configured BRCB/URCB is valid engineering inventory,
+/// but it is not a live acquisition source and therefore must not inflate the monitor with
+/// permanently unavailable rows. When an SCL workspace is open, its ReportControl bindings
+/// are the configuration authority; live discovery is verification only. For online-only
+/// operation with no SCL workspace, live discovery becomes the configuration authority.
+///
+/// A DataSetReference on a browsed/runtime alias is also not sufficient authority: several
 /// aliases can point at the same static FCDA/FCD member (for example cVal/instCVal or
-/// structured measurement descendants). Static mode must select one presentation row
-/// for each engine-authoritative DataSet membership, preserving the literal member
-/// identity that appears in SCL/ARIEC.
+/// structured measurement descendants). Static mode selects one presentation row for each
+/// engine-authoritative membership, preserving the literal member identity from SCL/ARIEC.
 /// </summary>
 public static class Iec61850StaticDataSetAuthoritySelection
 {
@@ -18,64 +24,108 @@ public static IReadOnlySet<SignalDefinition> Build(Iec61850MonitorDevice device)
     {
         ArgumentNullException.ThrowIfNull(device);
 
-        var model = device.LiveDiscoveryModel ?? device.SclWorkspace?.DesignModel;
-        if (model is null)
+        // Opened SCL is the engineering authority. A partial or richer live model may verify
+        // the configuration later, but it must not introduce extra static memberships that
+        // were never configured in the opened CID/SCD. Online-only mode falls back to live.
+        var authorityModel = device.SclWorkspace?.DesignModel ?? device.LiveDiscoveryModel;
+        if (authorityModel is null)
             return new HashSet<SignalDefinition>(ReferenceEqualityComparer.Instance);
 
-        var mandatory = Iec61850DataSetSignalInventoryProjection.GetMandatorySignals(model);
+        var reportBackedDataSets = BuildReportBackedDataSetReferences(device);
+        if (reportBackedDataSets.Count == 0)
+            return new HashSet<SignalDefinition>(ReferenceEqualityComparer.Instance);
+
+        var mandatory = Iec61850DataSetSignalInventoryProjection.GetMandatorySignals(authorityModel);
         var selected = new HashSet<SignalDefinition>(ReferenceEqualityComparer.Instance);
         var signals = device.Signals.ToArray();
 
         foreach (var descriptor in mandatory)
         {
-            var membership = descriptor.DataSetMemberships
+            // A descriptor may carry more than one membership. Do not arbitrarily take the
+            // first DataSet: choose only literal memberships that are backed by authoritative
+            // report-control configuration.
+            var memberships = descriptor.DataSetMemberships
+                .Where(item => reportBackedDataSets.Contains(NormalizeLiteral(item.DataSetReference)))
                 .OrderBy(item => item.DataSetReference, StringComparer.OrdinalIgnoreCase)
                 .ThenBy(item => item.MemberIndex)
-                .FirstOrDefault();
-            if (membership is null)
-                continue;
-
-            var memberReference = FirstNonEmpty(
-                membership.CanonicalMemberReference,
-                membership.OriginalMemberReference,
-                descriptor.DesignReference,
-                descriptor.ObservedReference,
-                descriptor.PrimaryValueReference);
-            if (string.IsNullOrWhiteSpace(memberReference) ||
-                string.IsNullOrWhiteSpace(membership.DataSetReference))
-                continue;
-
-            var candidates = signals
-                .Where(signal => !signal.IsControlSignal && signal.CanPublishToRuntime)
-                .Where(signal => LiteralEquals(signal.DataSetReference, membership.DataSetReference))
-                .Where(signal => LiteralEquals(signal.DisplayReference, memberReference))
                 .ToArray();
-            if (candidates.Length == 0)
-                continue;
-
-            // Prefer the runtime row already bound to ARIEC's resolved primary value.
-            // For an unresolved structured member, the inventory-created exact static row
-            // wins over a generic browsed alias. Never choose by fuzzy/prefix matching.
-            var chosen = candidates
-                .OrderByDescending(signal =>
-                    !string.IsNullOrWhiteSpace(descriptor.PrimaryValueReference) &&
-                    LiteralEquals(signal.ObjectReference, descriptor.PrimaryValueReference))
-                .ThenByDescending(signal =>
-                    (signal.Source ?? string.Empty).Contains(
-                        "mandatory static DataSet member",
-                        StringComparison.OrdinalIgnoreCase))
-                .ThenByDescending(signal =>
-                    string.Equals(signal.Category, "DataSet", StringComparison.OrdinalIgnoreCase))
-                .ThenByDescending(signal =>
-                    string.Equals(signal.Confidence, "High", StringComparison.OrdinalIgnoreCase))
-                .First();
-
-            selected.Add(chosen);
+
+            foreach (var membership in memberships)
+            {
+                var memberReference = FirstNonEmpty(
+                    membership.CanonicalMemberReference,
+                    membership.OriginalMemberReference,
+                    descriptor.DesignReference,
+                    descriptor.ObservedReference,
+                    descriptor.PrimaryValueReference);
+                if (string.IsNullOrWhiteSpace(memberReference) ||
+                    string.IsNullOrWhiteSpace(membership.DataSetReference))
+                {
+                    continue;
+                }
+
+                var candidates = signals
+                    .Where(signal => !signal.IsControlSignal && signal.CanPublishToRuntime)
+                    .Where(signal => LiteralEquals(signal.DataSetReference, membership.DataSetReference))
+                    .Where(signal => LiteralEquals(signal.DisplayReference, memberReference))
+                    .ToArray();
+                if (candidates.Length == 0)
+                    continue;
+
+                // Prefer the runtime row already bound to ARIEC's resolved primary value.
+                // For an unresolved structured member, the inventory-created exact static row
+                // wins over a generic browsed alias. Never choose by fuzzy/prefix matching.
+                var chosen = candidates
+                    .OrderByDescending(signal =>
+                        !string.IsNullOrWhiteSpace(descriptor.PrimaryValueReference) &&
+                        LiteralEquals(signal.ObjectReference, descriptor.PrimaryValueReference))
+                    .ThenByDescending(signal =>
+                        (signal.Source ?? string.Empty).Contains(
+                            "mandatory static DataSet member",
+                            StringComparison.OrdinalIgnoreCase))
+                    .ThenByDescending(signal =>
+                        string.Equals(signal.Category, "DataSet", StringComparison.OrdinalIgnoreCase))
+                    .ThenByDescending(signal =>
+                        string.Equals(signal.Confidence, "High", StringComparison.OrdinalIgnoreCase))
+                    .First();
+
+                selected.Add(chosen);
+            }
         }
 
         return selected;
     }
 
+    /// <summary>
+    /// Returns the literal DataSet references that have authoritative ReportControl backing.
+    /// Opened SCL configuration wins absolutely over extra live ReportControls. Live discovery
+    /// is used as configuration authority only when no SCL design model is open.
+    /// </summary>
+    public static IReadOnlySet<string> BuildReportBackedDataSetReferences(Iec61850MonitorDevice device)
+    {
+        ArgumentNullException.ThrowIfNull(device);
+
+        var result = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
+        var configurationModel = device.SclWorkspace?.DesignModel ?? device.LiveDiscoveryModel;
+        AddReportBackedDataSets(configurationModel, result);
+        return result;
+    }
+
+    private static void AddReportBackedDataSets(
+        LiveIedModelDiscoveryDocument? model,
+        HashSet<string> target)
+    {
+        if (model is null)
+            return;
+
+        foreach (var report in model.ReportControls)
+        {
+            var dataSetReference = NormalizeLiteral(report.DataSetReference);
+            if (!string.IsNullOrWhiteSpace(dataSetReference))
+                target.Add(dataSetReference);
+        }
+    }
+
     private static bool LiteralEquals(string? left, string? right)
         => string.Equals(NormalizeLiteral(left), NormalizeLiteral(right), StringComparison.OrdinalIgnoreCase);
 
diff --git a/Services/Iec61850StaticRcbReferenceMatcher.cs b/Services/Iec61850StaticRcbReferenceMatcher.cs
new file mode 100644
index 00000000..8adc6a7c
--- /dev/null
+++ b/Services/Iec61850StaticRcbReferenceMatcher.cs
@@ -0,0 +1,74 @@
+namespace ArIED61850Tester.Services;
+
+/// <summary>
+/// Matches one configured SCL ReportControl declaration to the concrete RCB object exposed
+/// by the live MMS server.
+///
+/// IEC 61850 SCL may describe one indexed ReportControl family while the server exposes
+/// concrete instances such as Buffer01 / Buffer02. Exact identity always wins. The only
+/// accepted fallback is a decimal indexed instance of the same literal RCB family; arbitrary
+/// same-DataSet RCBs are never treated as substitutes.
+/// </summary>
+public static class Iec61850StaticRcbReferenceMatcher
+{
+    public static bool IsExact(string? configuredReference, string? liveReference)
+        => string.Equals(
+            Normalize(configuredReference),
+            Normalize(liveReference),
+            StringComparison.OrdinalIgnoreCase);
+
+    public static bool IsConfiguredOrIndexedInstance(string? configuredReference, string? liveReference)
+    {
+        var configured = Normalize(configuredReference);
+        var live = Normalize(liveReference);
+        if (string.IsNullOrWhiteSpace(configured) || string.IsNullOrWhiteSpace(live))
+            return false;
+        if (string.Equals(configured, live, StringComparison.OrdinalIgnoreCase))
+            return true;
+
+        SplitLeaf(configured, out var configuredParent, out var configuredLeaf);
+        SplitLeaf(live, out var liveParent, out var liveLeaf);
+        if (!string.Equals(configuredParent, liveParent, StringComparison.OrdinalIgnoreCase) ||
+            string.IsNullOrWhiteSpace(configuredLeaf) ||
+            string.IsNullOrWhiteSpace(liveLeaf))
+        {
+            return false;
+        }
+
+        // If the configured declaration already ends in a digit, treat it as a concrete
+        // object and require exact identity. This avoids accidental prefix matches such as
+        // Buffer0 -> Buffer01.
+        if (char.IsDigit(configuredLeaf[^1]) ||
+            !liveLeaf.StartsWith(configuredLeaf, StringComparison.OrdinalIgnoreCase))
+        {
+            return false;
+        }
+
+        var suffix = liveLeaf[configuredLeaf.Length..];
+        return suffix.Length > 0 && suffix.All(char.IsDigit);
+    }
+
+    public static int MatchRank(string? configuredReference, string? liveReference)
+    {
+        if (IsExact(configuredReference, liveReference))
+            return 0;
+        return IsConfiguredOrIndexedInstance(configuredReference, liveReference) ? 1 : int.MaxValue;
+    }
+
+    public static string Normalize(string? reference)
+        => (reference ?? string.Empty).Trim().Replace('$', '.');
+
+    private static void SplitLeaf(string reference, out string parent, out string leaf)
+    {
+        var separator = reference.LastIndexOf('.');
+        if (separator < 0)
+        {
+            parent = string.Empty;
+            leaf = reference;
+            return;
+        }
+
+        parent = reference[..separator];
+        leaf = reference[(separator + 1)..];
+    }
+}
diff --git a/Services/NativeIec61850Client.StaticDataSetReporting.cs b/Services/NativeIec61850Client.StaticDataSetReporting.cs
index 68cdcd9b..32d5173a 100644
--- a/Services/NativeIec61850Client.StaticDataSetReporting.cs
+++ b/Services/NativeIec61850Client.StaticDataSetReporting.cs
@@ -1,3 +1,4 @@
+using AR.Iec61850.Discovery;
 using ArIED61850Tester.Models;
 using ArMms = AR.Iec61850.Mms;
 
@@ -9,9 +10,10 @@ namespace ArIED61850Tester.Services;
 /// Static mode already has complete configuration authority in the opened/live SCL model:
 /// exact DataSet membership and configured RCB -> DataSet bindings. Do not run those facts
 /// through the adaptive Hybrid acquisition planner. The live association is used only to
-/// verify that the exact configured RCB and exact DataSet directory exist, then ARIEC's
-/// persistent monitor installs the InformationReport receiver, enables RptEna and requests
-/// GI. No dynamic DataSet write and no cyclic process-value MMS read is permitted here.
+/// verify that the configured RCB (or a concrete indexed instance of that configured family)
+/// and exact DataSet directory exist, then ARIEC's persistent monitor installs the
+/// InformationReport receiver, enables RptEna and requests GI. No dynamic DataSet write and
+/// no cyclic process-value MMS read is permitted here.
 /// </summary>
 public sealed partial class NativeIec61850Client
 {
@@ -30,8 +32,10 @@ public async Task<NativeHybridReportPlanningResult> BuildStaticDataSetReportPlan
         _deterministicStaticSubscriptions.Clear();
         ResetSemanticReportProjectionContext();
 
-        var model = device.LiveDiscoveryModel ?? device.SclWorkspace?.DesignModel;
-        if (model is null)
+        // Opened SCL is the semantic and configuration authority. A live model is authoritative
+        // only for online-only operation where no CID/SCD workspace is open.
+        var projectionModel = device.SclWorkspace?.DesignModel ?? device.LiveDiscoveryModel;
+        if (projectionModel is null)
         {
             return StaticPlanningUnavailable(
                 points,
@@ -45,12 +49,22 @@ public async Task<NativeHybridReportPlanningResult> BuildStaticDataSetReportPlan
                 $"Static DataSet report-only requires an initiated MMS association. Current state: {_session.State}.");
         }
 
-        SetSemanticReportProjectionAuthority(model);
+        SetSemanticReportProjectionAuthority(projectionModel);
+
+        // P0 authority rule: when an SCL workspace exists, only ReportControls from that
+        // design model may authorize static acquisition. Fresh live discovery is verification
+        // and concrete-instance evidence; it must never introduce a peer RCB that can displace
+        // an explicit SCL binding such as Digital -> Buffer02.
+        var configurationModel = projectionModel;
+        var configurationAuthorityLabel = device.SclWorkspace?.DesignModel is not null
+            ? "opened SCL design model"
+            : "live discovery model (online-only)";
 
         // Fresh report discovery is verification, not permission policy. In particular we
-        // deliberately do NOT classify a configured BRCB through the Hybrid availability
-        // confidence gate. Some perfectly usable servers expose RptEna and DatSet but omit
-        // enough reservation metadata for that adaptive gate to call the RCB 'Available'.
+        // deliberately do NOT require the adaptive Hybrid availability gate to classify a
+        // configured BRCB as Available. Some perfectly usable servers omit enough reservation
+        // metadata to remain Unknown. Explicit enabled/reserved/owner evidence is still used
+        // to avoid stealing an occupied RCB.
         var discovery = await EnsureDiscoveryForReportingAsync(cancellationToken).ConfigureAwait(false);
         if (discovery is null)
         {
@@ -61,6 +75,11 @@ public async Task<NativeHybridReportPlanningResult> BuildStaticDataSetReportPlan
                     : LastErrorMessage);
         }
 
+        var callerOwnedRcbReferences = _reportMonitorSessions.Values
+            .Select(session => NormalizeStaticReference(session.ReportControl.Reference))
+            .Where(reference => !string.IsNullOrWhiteSpace(reference))
+            .ToHashSet(StringComparer.OrdinalIgnoreCase);
+
         var reportPlans = new List<ReportControlPlan>();
         var warnings = new List<string>();
         var coveredPointKeys = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
@@ -76,8 +95,13 @@ public async Task<NativeHybridReportPlanningResult> BuildStaticDataSetReportPlan
         {
             cancellationToken.ThrowIfCancellationRequested();
 
-            var configuredReports = model.ReportControls
+            var dataSetReference = dataSetGroup.First().DataSetReference.Trim();
+            var configuredReports = configurationModel.ReportControls
                 .Where(report => SameStaticReference(report.DataSetReference, dataSetGroup.Key))
+                .GroupBy(
+                    report => $"{NormalizeStaticReference(report.Reference)}|{NormalizeStaticReference(report.DataSetReference)}",
+                    StringComparer.OrdinalIgnoreCase)
+                .Select(group => group.First())
                 .OrderByDescending(report => report.Buffered)
                 .ThenBy(report => report.Reference, StringComparer.OrdinalIgnoreCase)
                 .ToArray();
@@ -85,42 +109,129 @@ public async Task<NativeHybridReportPlanningResult> BuildStaticDataSetReportPlan
             if (configuredReports.Length == 0)
             {
                 warnings.Add(
-                    $"{dataSetGroup.First().DataSetReference}: no configured BRCB/URCB in the SCL model; {dataSetGroup.Count()} selected point(s) remain explicitly unavailable. No MMS process polling was substituted.");
+                    $"{dataSetReference}: no configured BRCB/URCB in the authoritative {configurationAuthorityLabel}; {dataSetGroup.Count()} selected point(s) remain explicitly unavailable. No MMS process polling was substituted.");
                 continue;
             }
 
-            if (configuredReports.Length > 1)
-            {
-                warnings.Add(
-                    $"{dataSetGroup.First().DataSetReference}: {configuredReports.Length} configured RCBs reference this DataSet; deterministic Static mode selected {configuredReports[0].Reference} (BRCB preferred, then literal reference order)." );
-            }
+            // Evaluate every authoritative configured RCB instead of selecting only the first.
+            // If several SCL ReportControls legitimately reference the same DataSet, one
+            // missing/occupied RCB must not hide another configured option. A configured family
+            // may resolve only to decimal indexed instances of that same literal family;
+            // arbitrary same-DataSet substitution remains forbidden.
+            var matchedLiveCandidates = configuredReports
+                .SelectMany(configured => discovery.ReportInventory.ReportControls
+                    .Select(candidate => new
+                    {
+                        Configured = configured,
+                        Candidate = candidate,
+                        Rank = Iec61850StaticRcbReferenceMatcher.MatchRank(
+                            configured.Reference,
+                            candidate.Reference)
+                    })
+                    .Where(item => item.Rank != int.MaxValue)
+                    .Where(item =>
+                        string.IsNullOrWhiteSpace(item.Candidate.DataSetReference) ||
+                        SameStaticReference(item.Candidate.DataSetReference, dataSetReference)))
+                .OrderBy(item => item.Rank)
+                .ThenByDescending(item => item.Configured.Buffered)
+                .ThenBy(item => item.Configured.Reference, StringComparer.OrdinalIgnoreCase)
+                .ThenBy(item => item.Candidate.Reference, StringComparer.OrdinalIgnoreCase)
+                .ToArray();
+
+            // Use ARIEC's operational evaluator so Owner is part of the same occupancy
+            // decision as RptEna/Resv/ResvTms. Directory evidence is intentionally omitted at
+            // this stage: Unknown is still eligible and the exact DataSet directory is verified
+            // before the plan is armed. If a currently active session already owns the RCB,
+            // preserve that fact as UsedByCaller instead of misclassifying it as foreign use.
+            var evaluatedLiveCandidates = matchedLiveCandidates
+                .Select(item => new
+                {
+                    item.Configured,
+                    item.Candidate,
+                    item.Rank,
+                    Availability = ArMms.MmsRcbAvailabilityEvaluator.Evaluate(
+                        item.Candidate,
+                        dataSetDirectory: null,
+                        callerOwned: callerOwnedRcbReferences.Contains(
+                            NormalizeStaticReference(item.Candidate.Reference)))
+                })
+                .ToArray();
 
-            var configured = configuredReports[0];
-            var liveCandidates = discovery.ReportInventory.ReportControls
-                .Where(candidate => SameStaticReference(candidate.Reference, configured.Reference))
+            // An indexed family can expose several concrete RCBs. Literal instance order is
+            // not an activation policy: Buffer01 may already be enabled/reserved/owned while
+            // Buffer02 is the usable instance. Reject only explicit operational blockers;
+            // Unknown remains eligible because some relays omit reservation metadata. Among
+            // equally matched candidates prefer exact identity, caller-owned/known-safe state,
+            // BRCB, explicitly disabled state, and finally stable literal order.
+            var liveCandidates = evaluatedLiveCandidates
+                .Where(item => StaticRcbAvailabilityRank(item.Availability.Availability) != int.MaxValue)
+                .Where(item => !ArMms.MmsReportSubscriptionPlanner.IsExplicitlyEnabled(item.Candidate))
+                .Where(item => !ArMms.MmsReportSubscriptionPlanner.IsReservedByOtherClient(item.Candidate))
+                .OrderBy(item => item.Rank)
+                .ThenBy(item => StaticRcbAvailabilityRank(item.Availability.Availability))
+                .ThenByDescending(item => item.Configured.Buffered)
+                .ThenByDescending(item => ArMms.MmsReportSubscriptionPlanner.IsExplicitlyDisabled(item.Candidate))
+                .ThenBy(item => item.Configured.Reference, StringComparer.OrdinalIgnoreCase)
+                .ThenBy(item => item.Candidate.Reference, StringComparer.OrdinalIgnoreCase)
                 .ToArray();
 
-            if (liveCandidates.Length != 1)
+            if (liveCandidates.Length == 0)
             {
+                if (evaluatedLiveCandidates.Length > 0)
+                {
+                    var occupied = string.Join(
+                        ", ",
+                        evaluatedLiveCandidates.Take(8).Select(item =>
+                            $"{item.Configured.Reference}->{item.Candidate.Reference}[availability={item.Availability.Availability}, RptEna={item.Candidate.EnabledState}, Resv={item.Candidate.ReservationState}, ResvTms={item.Candidate.ReservationTimeSeconds}, Owner={item.Candidate.Owner}]"));
+                    warnings.Add(
+                        $"{dataSetReference}: exact/indexed-family RCB objects were found for authoritative configuration, but every concrete instance was explicitly unavailable/in-use ({occupied}). Static mode will not steal an occupied RCB and did not poll process values.");
+                    continue;
+                }
+
+                var configuredNames = string.Join(", ", configuredReports
+                    .Select(report => report.Reference)
+                    .Where(reference => !string.IsNullOrWhiteSpace(reference))
+                    .Take(8));
+                var sameDataSet = discovery.ReportInventory.ReportControls
+                    .Where(candidate =>
+                        !string.IsNullOrWhiteSpace(candidate.DataSetReference) &&
+                        SameStaticReference(candidate.DataSetReference, dataSetReference))
+                    .Select(candidate => candidate.Reference)
+                    .Where(reference => !string.IsNullOrWhiteSpace(reference))
+                    .OrderBy(reference => reference, StringComparer.OrdinalIgnoreCase)
+                    .Take(8)
+                    .ToArray();
+                var observed = sameDataSet.Length == 0
+                    ? "none"
+                    : string.Join(", ", sameDataSet);
                 warnings.Add(
-                    $"{configured.Reference}: configured RCB was proven by SCL but exact live MMS discovery returned {liveCandidates.Length} matching RCB object(s). Static mode refused to guess and did not poll process values.");
+                    $"{dataSetReference}: authoritative configured RCB(s) [{configuredNames}] had no exact/indexed-family live instance. Same-DataSet live RCBs: {observed}. Static mode refused arbitrary substitution and did not poll process values.");
                 continue;
             }
 
-            var liveRcb = CloneReportControlForPlanning(liveCandidates[0]);
-            var dataSetReference = dataSetGroup.First().DataSetReference.Trim();
+            var selected = liveCandidates[0];
+            var configured = selected.Configured;
+            var liveSource = selected.Candidate;
+            var liveAvailability = selected.Availability;
+            var liveRcb = CloneReportControlForPlanning(liveSource);
+
+            if (configuredReports.Length > 1 || liveCandidates.Length > 1)
+            {
+                warnings.Add(
+                    $"{dataSetReference}: evaluated {configuredReports.Length} authoritative configured RCB(s) and {liveCandidates.Length} non-occupied exact/indexed live match(es); selected {configured.Reference} -> {liveSource.Reference} ({liveAvailability.Availability}). {configurationAuthorityLabel} remained authoritative.");
+            }
 
             if (!string.IsNullOrWhiteSpace(liveRcb.DataSetReference) &&
                 !SameStaticReference(liveRcb.DataSetReference, dataSetReference))
             {
                 warnings.Add(
-                    $"{configured.Reference}: SCL binds {dataSetReference}, but live DatSet reports {liveRcb.DataSetReference}. Static mode refused the mismatch instead of guessing or polling.");
+                    $"{configured.Reference}: authoritative configuration binds {dataSetReference}, but live DatSet reports {liveRcb.DataSetReference}. Static mode refused the mismatch instead of guessing or polling.");
                 continue;
             }
 
-            // Missing live DatSet text is not treated as a reason to discard correct SCL
-            // configuration. The exact DataSet directory below is still required and is the
-            // ordered mapping authority for InformationReport values.
+            // Missing live DatSet text is not treated as a reason to discard correct
+            // authoritative configuration. The exact DataSet directory below is still required
+            // and is the ordered mapping authority for InformationReport values.
             if (string.IsNullOrWhiteSpace(liveRcb.DataSetReference))
                 liveRcb.DataSetReference = dataSetReference;
 
@@ -149,13 +260,16 @@ public async Task<NativeHybridReportPlanningResult> BuildStaticDataSetReportPlan
             if (bindings.Count == 0)
                 continue;
 
+            var concreteReportReference = string.IsNullOrWhiteSpace(liveRcb.Reference)
+                ? configured.Reference
+                : liveRcb.Reference;
             var plan = new ReportControlPlan
             {
                 RelayId = device.DeviceId,
                 RelayName = device.Name,
                 RelayIpAddress = device.IpAddress,
                 IedName = device.Name,
-                ReportControlReference = configured.Reference,
+                ReportControlReference = concreteReportReference,
                 DataSetReference = dataSetReference,
                 Mode = "Static DataSet • deterministic configured RCB",
                 AllowDynamicDataSetWrites = false,
@@ -171,10 +285,20 @@ public async Task<NativeHybridReportPlanningResult> BuildStaticDataSetReportPlan
             };
 
             var subscriptionWarnings = new List<string>();
-            if (string.IsNullOrWhiteSpace(liveCandidates[0].DataSetReference))
+            if (!Iec61850StaticRcbReferenceMatcher.IsExact(configured.Reference, concreteReportReference))
+            {
+                subscriptionWarnings.Add(
+                    $"Configured ReportControl family {configured.Reference} resolved to concrete live indexed instance {concreteReportReference}.");
+            }
+            if (liveAvailability.Availability == ArMms.MmsRcbOperationalAvailability.Unknown)
             {
                 subscriptionWarnings.Add(
-                    "Live RCB DatSet text was not returned; exact SCL RCB->DataSet configuration plus the successfully read live DataSet directory are the deterministic authority.");
+                    $"Live RCB availability for {concreteReportReference} remains Unknown ({liveAvailability.Reason}). Static mode permits this because identity/configuration are authoritative and no explicit in-use evidence was observed.");
+            }
+            if (string.IsNullOrWhiteSpace(liveSource.DataSetReference))
+            {
+                subscriptionWarnings.Add(
+                    "Live RCB DatSet text was not returned; exact authoritative RCB->DataSet configuration plus the successfully read live DataSet directory are the deterministic authority.");
             }
 
             var subscription = new ArMms.MmsReportSubscriptionPlan
@@ -187,7 +311,7 @@ public async Task<NativeHybridReportPlanningResult> BuildStaticDataSetReportPlan
                 DynamicPoints = Array.Empty<ArMms.MmsFcResolvedPoint>(),
                 Steps = new[]
                 {
-                    $"Verify exact configured RCB {configured.Reference} exists on the live association.",
+                    $"Verify authoritative configured RCB {configured.Reference} as live object {concreteReportReference}.",
                     $"Use exact ordered live DataSet directory {dataSetReference} ({directory.Members.Count} members).",
                     "Install InformationReport receiver before enabling the RCB.",
                     "Write RptEna=true, then request GI=true.",
@@ -384,6 +508,15 @@ private static NativeHybridReportPlanningResult StaticPlanningUnavailable(
             UncoveredSignalCount = points.Count
         };
 
+    private static int StaticRcbAvailabilityRank(ArMms.MmsRcbOperationalAvailability availability)
+        => availability switch
+        {
+            ArMms.MmsRcbOperationalAvailability.UsedByCaller => 0,
+            ArMms.MmsRcbOperationalAvailability.Available => 1,
+            ArMms.MmsRcbOperationalAvailability.Unknown => 2,
+            _ => int.MaxValue
+        };
+
     private static bool SameStaticReference(string? left, string? right)
         => string.Equals(
             NormalizeStaticReference(left),
@@ -391,7 +524,7 @@ private static bool SameStaticReference(string? left, string? right)
             StringComparison.OrdinalIgnoreCase);
 
     private static string NormalizeStaticReference(string? reference)
-        => (reference ?? string.Empty).Trim().Replace('$', '.');
+        => Iec61850StaticRcbReferenceMatcher.Normalize(reference);
 
     private static int ParseStaticInteger(string? value)
         => int.TryParse(value, out var parsed) && parsed > 0 ? parsed : 0;
diff --git a/engines/ARIEC61850.lock.json b/engines/ARIEC61850.lock.json
index 5d8014d0..94c589a8 100644
--- a/engines/ARIEC61850.lock.json
+++ b/engines/ARIEC61850.lock.json
@@ -2,7 +2,7 @@
   "schemaVersion": 1,
   "repository": "masarray/ARIEC61850",
   "ref": "main",
-  "commit": "69bfe70e2c779c7e8268af087bd1a3a38986c0fc",
+  "commit": "0d7525bd330900917fb9f6d15a46059dc3d7a70a",
   "sourcePullRequest": 111,
-  "purpose": "Pins the exact ARIEC61850 engine used by ARSAS while preserving the reviewed reporting/control ancestry. PR #76 preserves unresolved static DataSet members; PR #77 canonicalizes cross-logical-device SCL references; PR #78 keeps one descriptor per static DataSet member while separating the resolved runtime primary leaf from original FCDA/FCD identity; PR #79 projects generic Boolean status structures to scalar stVal while preserving quality/timestamp; PR #80 normalizes validated DataRef-enabled InformationReport ordering; PR #81 accepts valid zero OptFlds reports while quarantining unmapped canonical report metadata; PR #84 routes exact PrimaryValue residuals through dynamic reporting before MMS polling; PR #85 evaluates association capabilities before automatic dynamic mutation; PR #86 records dynamic-attempt failure/skip evidence and best-effort rollback. PR #87 restores baseline-safe static precedence. PR #88 adds a fail-closed single-member DefineNamedVariableList -> GetNamedVariableListAttributes -> DeleteNamedVariableList probation with exact invoke/request/response/routing/member/association/cleanup evidence. PR #89 quarantines automatic full dynamic DataSet activation because a successful one-member NVL probation does not guarantee association survival; it also preserves safe instMag/mag and instCVal/cVal projection while ambiguous structures remain raw. PR #90 / field-proven engine a18e550d07f7bbe4ff7753c180b02615075f6292 preserves G1/G1.1 Smart Control: signed primitive constraints, ordered SBO/SBOw-to-Operate wire evidence, StationControl origin compatibility, and explicit MMS Write DataAccessError including object-access-denied. G2 PR #91 adds qualification-only bounded multi-member DefineNamedVariableList/GetNamedVariableListAttributes/DeleteNamedVariableList evidence with exact ordered read-back, encoded request/PDU evidence and fail-closed cleanup; PR #92 adds the 1/4/8/16/32 qualification ladder, deterministic bisection and explicit EnvelopeQualified acceptance; PR #93 adds a default-disabled ExplicitCommissioning coordinator with hard attempt budget, exact-set failure localization and fresh-association stop semantics; PR #94 adds identity-bound qualification profiles and prevents ProductionEligible unless RCB activation, an actual correctly mapped InformationReport, and all G2.6 physical regression gates are proven. G2.4 engine PR #95 retains the commissioning-only transactional URCB TrgOps/OptFlds lease. P0 physically proved the corrected IEC 61850 MMS TrgOps reserved-bit mapping: bit 0 reserved, bits 1..5 dchg/qchg/dupd/integrity/GI, so dchg+GI encodes canonically as 0244; P0 also separates raw BER equality from IEC significant-bit equality and provides a one-URCB TrgOps-only micro-probe that never writes OptFlds, DatSet, Resv, RptEna, GI or any DataSet service. P1 adds a dedicated one-URCB OptFlds-only capture/write/readback/finally-restore micro-probe for reason-for-inclusion + data-set-name, canonical target 061800, using ten-bit significant-value comparison while never writing TrgOps, DatSet, Resv, RptEna, GI, Define/Delete DataSet, starting a report monitor, or changing profile state. The G2.4 Owner correction exposes the exact local TCP address of the active MMS association and fail-closed decodes a server RCB Owner as a 4-byte IPv4 or 16-byte IPv6 address; physical SIPROTEC Owner C0A851F0 decodes to 192.168.81.240 and may prove caller ownership only when it exactly matches the active local TCP endpoint. Owner mismatch or unsupported encoding remains a hard failure. Original RCB values remain captured for restore, raw BER evidence is retained, and Production automatic dynamic BRCB/URCB activation remains quarantined until a compatible ProductionEligible profile is consumed by a later G2 phase. FAT P5.3 engine PR #103 resolves intermediate structured static DataSet members such as MMXU A.phsA and PPV.phsAB only to typed descendants below the exact FCDA boundary, selects a unique semantic primary runtime leaf such as cVal.mag.f without crossing sibling phases, preserves original static membership identity, and leaves genuinely ambiguous structures unresolved rather than guessing. FAT P5.4 engine PR #106 adds fail-closed model-backed InformationReport projection for structured static DataSet members: an exact report member reference now resolves independently of sparse decoder-side report value position, while DataSet scope still prevents duplicate static memberships from collapsing; when a report omits the member reference, static DataSet index remains the unique fail-closed fallback. All schema-proven scalar descendants are fanned out without selecting a sibling phase, and schema mismatch preserves raw projection instead of guessing. ARSAS supplies the per-IED LiveDiscovery/SCL planning model at the report receive seam. PR #111 is a narrow continuation on the exact b9ee5fc ARSAS engine baseline: exact static DataSet/SCL semantic schema is now attempted before generic structured-value heuristics so TotPF and similar members can publish their exact scalar leaves; generic projection remains the fail-closed fallback, and report q/t companions are ordered ahead of semantic scalar values so ARSAS can preserve relay-native quality/timestamp without MMS polling."
+  "purpose": "Pins the exact ARIEC61850 engine used by ARSAS while preserving the reviewed reporting/control ancestry. PR #76 preserves unresolved static DataSet members; PR #77 canonicalizes cross-logical-device SCL references; PR #78 keeps one descriptor per static DataSet member while separating the resolved runtime primary leaf from original FCDA/FCD identity; PR #79 projects generic Boolean status structures to scalar stVal while preserving quality/timestamp; PR #80 normalizes validated DataRef-enabled InformationReport ordering; PR #81 accepts valid zero OptFlds reports while quarantining unmapped canonical report metadata; PR #84 routes exact PrimaryValue residuals through dynamic reporting before MMS polling; PR #85 evaluates association capabilities before automatic dynamic mutation; PR #86 records dynamic-attempt failure/skip evidence and best-effort rollback. PR #87 restores baseline-safe static precedence. PR #88 adds a fail-closed single-member DefineNamedVariableList -> GetNamedVariableListAttributes -> DeleteNamedVariableList probation with exact invoke/request/response/routing/member/association/cleanup evidence. PR #89 quarantines automatic full dynamic DataSet activation because a successful one-member NVL probation does not guarantee association survival; it also preserves safe instMag/mag and instCVal/cVal projection while ambiguous structures remain raw. PR #90 / field-proven engine a18e550d07f7bbe4ff7753c180b02615075f6292 preserves G1/G1.1 Smart Control: signed primitive constraints, ordered SBO/SBOw-to-Operate wire evidence, StationControl origin compatibility, and explicit MMS Write DataAccessError including object-access-denied. G2 PR #91 adds qualification-only bounded multi-member DefineNamedVariableList/GetNamedVariableListAttributes/DeleteNamedVariableList evidence with exact ordered read-back, encoded request/PDU evidence and fail-closed cleanup; PR #92 adds the 1/4/8/16/32 qualification ladder, deterministic bisection and explicit EnvelopeQualified acceptance; PR #93 adds a default-disabled ExplicitCommissioning coordinator with hard attempt budget, exact-set failure localization and fresh-association stop semantics; PR #94 adds identity-bound qualification profiles and prevents ProductionEligible unless RCB activation, an actual correctly mapped InformationReport, and all G2.6 physical regression gates are proven. G2.4 engine PR #95 retains the commissioning-only transactional URCB TrgOps/OptFlds lease. P0 physically proved the corrected IEC 61850 MMS TrgOps reserved-bit mapping: bit 0 reserved, bits 1..5 dchg/qchg/dupd/integrity/GI, so dchg+GI encodes canonically as 0244; P0 also separates raw BER equality from IEC significant-bit equality and provides a one-URCB TrgOps-only micro-probe that never writes OptFlds, DatSet, Resv, RptEna, GI or any DataSet service. P1 adds a dedicated one-URCB OptFlds-only capture/write/readback/finally-restore micro-probe for reason-for-inclusion + data-set-name, canonical target 061800, using ten-bit significant-value comparison while never writing TrgOps, DatSet, Resv, RptEna, GI, Define/Delete DataSet, starting a report monitor, or changing profile state. The G2.4 Owner correction exposes the exact local TCP address of the active MMS association and fail-closed decodes a server RCB Owner as a 4-byte IPv4 or 16-byte IPv6 address; physical SIPROTEC Owner C0A851F0 decodes to 192.168.81.240 and may prove caller ownership only when it exactly matches the active local TCP endpoint. Owner mismatch or unsupported encoding remains a hard failure. Original RCB values remain captured for restore, raw BER evidence is retained, and Production automatic dynamic BRCB/URCB activation remains quarantined until a compatible ProductionEligible profile is consumed by a later G2 phase. FAT P5.3 engine PR #103 resolves intermediate structured static DataSet members such as MMXU A.phsA and PPV.phsAB only to typed descendants below the exact FCDA boundary, selects a unique semantic primary runtime leaf such as cVal.mag.f without crossing sibling phases, preserves original static membership identity, and leaves genuinely ambiguous structures unresolved rather than guessing. FAT P5.4 engine PR #106 adds fail-closed model-backed InformationReport projection for structured static DataSet members: an exact report member reference now resolves independently of sparse decoder-side report value position, while DataSet scope still prevents duplicate static memberships from collapsing; when a report omits the member reference, static DataSet index remains the unique fail-closed fallback. All schema-proven scalar descendants are fanned out without selecting a sibling phase, and schema mismatch preserves raw projection instead of guessing. ARSAS supplies the per-IED LiveDiscovery/SCL planning model at the report receive seam. PR #111 is a narrow continuation on the exact b9ee5fc ARSAS engine baseline: exact static DataSet/SCL semantic schema is attempted before generic structured-value heuristics so TotPF and similar members publish exact scalar leaves; generic projection remains the fail-closed fallback, and report q/t companions are ordered ahead of semantic scalar values. P1 hardening at 0d7525bd330900917fb9f6d15a46059dc3d7a70a also makes semantic expansion return the resolved authoritative member identity and replaces generic output by report-value position after semantic success, so an InformationReport that omits MemberReference but resolves uniquely through static DataSet index cannot leak unrooted projected-mx-pair leaves alongside exact semantic values."
 }
diff --git a/tests/ARSAS.Tests/DeterministicStaticReportPathRegressionTests.cs b/tests/ARSAS.Tests/DeterministicStaticReportPathRegressionTests.cs
index af8ab324..ac7637b0 100644
--- a/tests/ARSAS.Tests/DeterministicStaticReportPathRegressionTests.cs
+++ b/tests/ARSAS.Tests/DeterministicStaticReportPathRegressionTests.cs
@@ -8,7 +8,8 @@ public void StaticPath_BypassesAdaptiveHybridPlannerAndPolling()
         var source = Read("Services/NativeIec61850Client.StaticDataSetReporting.cs");
 
         Assert.Contains("Deterministic Static DataSet configured-RCB path", source, StringComparison.Ordinal);
-        Assert.Contains("model.ReportControls", source, StringComparison.Ordinal);
+        Assert.Contains("var configurationModel = projectionModel", source, StringComparison.Ordinal);
+        Assert.Contains("configurationModel.ReportControls", source, StringComparison.Ordinal);
         Assert.Contains("discovery.ReportInventory.ReportControls", source, StringComparison.Ordinal);
         Assert.Contains("GetDataSetDirectoriesAsync", source, StringComparison.Ordinal);
         Assert.Contains("MmsReportSubscriptionPlanStatus.ReadyRequiresWrite", source, StringComparison.Ordinal);
@@ -17,6 +18,7 @@ public void StaticPath_BypassesAdaptiveHybridPlannerAndPolling()
         Assert.Contains("PollingPointKeys = Array.Empty<string>()", source, StringComparison.Ordinal);
         Assert.Contains("PollingFallbackSignalCount = 0", source, StringComparison.Ordinal);
 
+        Assert.DoesNotContain("configurationModels", source, StringComparison.Ordinal);
         Assert.DoesNotContain("MmsCapabilityAwareHybridReportAcquisitionPlanner", source, StringComparison.Ordinal);
         Assert.DoesNotContain("BuildDynamicPlan", source, StringComparison.Ordinal);
         Assert.DoesNotContain("DefineNamedVariableList", source, StringComparison.Ordinal);
@@ -24,17 +26,53 @@ public void StaticPath_BypassesAdaptiveHybridPlannerAndPolling()
     }
 
     [Fact]
-    public void StaticPath_RequiresExactConfiguredRcbAndOrderedLiveDataSetDirectory()
+    public void StaticPath_RequiresConfiguredRcbFamilyAndOrderedLiveDataSetDirectory()
     {
         var source = Read("Services/NativeIec61850Client.StaticDataSetReporting.cs");
 
         Assert.Contains("SameStaticReference(report.DataSetReference, dataSetGroup.Key)", source, StringComparison.Ordinal);
-        Assert.Contains("SameStaticReference(candidate.Reference, configured.Reference)", source, StringComparison.Ordinal);
+        Assert.Contains("Iec61850StaticRcbReferenceMatcher.MatchRank", source, StringComparison.Ordinal);
+        Assert.Contains("arbitrary same-DataSet", source, StringComparison.OrdinalIgnoreCase);
         Assert.Contains("live DataSet directory could not prove an ordered non-empty member list", source, StringComparison.Ordinal);
         Assert.Contains("directory.Members", source, StringComparison.Ordinal);
         Assert.Contains("No MMS process polling was substituted", source, StringComparison.Ordinal);
-        Assert.Contains("SCL binds", source, StringComparison.Ordinal);
+        Assert.Contains("authoritative configuration binds", source, StringComparison.Ordinal);
         Assert.Contains("live DatSet reports", source, StringComparison.Ordinal);
+        Assert.Contains("ReportControlReference = concreteReportReference", source, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void StaticPath_SclAuthorityCannotBeDisplacedByLivePeerRcb()
+    {
+        var source = Read("Services/NativeIec61850Client.StaticDataSetReporting.cs");
+
+        Assert.Contains("device.SclWorkspace?.DesignModel ?? device.LiveDiscoveryModel", source, StringComparison.Ordinal);
+        Assert.Contains("only ReportControls from that", source, StringComparison.Ordinal);
+        Assert.Contains("design model may authorize static acquisition", source, StringComparison.Ordinal);
+        Assert.Contains("var configurationModel = projectionModel", source, StringComparison.Ordinal);
+        Assert.Contains("SelectMany(configured => discovery.ReportInventory.ReportControls", source, StringComparison.Ordinal);
+        Assert.DoesNotContain("SelectMany(configurationModel => configurationModel.ReportControls)", source, StringComparison.Ordinal);
+        Assert.DoesNotContain("var configured = configuredReports[0]", source, StringComparison.Ordinal);
+        Assert.Contains("remained authoritative", source, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void IndexedRcbFamily_PrefersNonOccupiedConcreteInstance()
+    {
+        var source = Read("Services/NativeIec61850Client.StaticDataSetReporting.cs");
+
+        Assert.Contains("matchedLiveCandidates", source, StringComparison.Ordinal);
+        Assert.Contains("evaluatedLiveCandidates", source, StringComparison.Ordinal);
+        Assert.Contains("MmsRcbAvailabilityEvaluator.Evaluate", source, StringComparison.Ordinal);
+        Assert.Contains("callerOwnedRcbReferences", source, StringComparison.Ordinal);
+        Assert.Contains("MmsReportSubscriptionPlanner.IsExplicitlyEnabled(item.Candidate)", source, StringComparison.Ordinal);
+        Assert.Contains("MmsReportSubscriptionPlanner.IsReservedByOtherClient(item.Candidate)", source, StringComparison.Ordinal);
+        Assert.Contains("MmsReportSubscriptionPlanner.IsExplicitlyDisabled(item.Candidate)", source, StringComparison.Ordinal);
+        Assert.Contains("StaticRcbAvailabilityRank", source, StringComparison.Ordinal);
+        Assert.Contains("Owner={item.Candidate.Owner}", source, StringComparison.Ordinal);
+        Assert.Contains("every concrete instance was explicitly unavailable/in-use", source, StringComparison.Ordinal);
+        Assert.Contains("Static mode will not steal an occupied RCB", source, StringComparison.Ordinal);
+        Assert.Contains("prefer exact identity, caller-owned/known-safe state", source, StringComparison.Ordinal);
     }
 
     [Fact]
diff --git a/tests/ARSAS.Tests/FatScrollStabilityRegressionTests.cs b/tests/ARSAS.Tests/FatScrollStabilityRegressionTests.cs
new file mode 100644
index 00000000..56d23d3e
--- /dev/null
+++ b/tests/ARSAS.Tests/FatScrollStabilityRegressionTests.cs
@@ -0,0 +1,100 @@
+namespace ARSAS.Tests;
+
+public sealed class FatScrollStabilityRegressionTests
+{
+    [Fact]
+    public void Recovery_KeepsBuild1868Value1Value2GridContract()
+    {
+        var ux = File.ReadAllText(FindRepoFile("IoListTestingWindow.FatV2Ux.cs"));
+
+        Assert.Contains("Header = \"TEST\"", ux, StringComparison.Ordinal);
+        Assert.Contains("TextColumn(\"SIGNAL\"", ux, StringComparison.Ordinal);
+        Assert.Contains("TextColumn(\"IEC REFERENCE\"", ux, StringComparison.Ordinal);
+        Assert.Contains("TextColumn(\"TYPE\"", ux, StringComparison.Ordinal);
+        Assert.Contains("Header = \"LIVE VALUE\"", ux, StringComparison.Ordinal);
+        Assert.Contains("Header = slot == FatValueSlot.Value1 ? \"VALUE 1\" : \"VALUE 2\"", ux, StringComparison.Ordinal);
+        Assert.Contains("TextColumn(\"STATUS\"", ux, StringComparison.Ordinal);
+        Assert.Contains("TextColumn(\"RESULT\"", ux, StringComparison.Ordinal);
+        Assert.DoesNotContain("ON · RELAY TIME", ux, StringComparison.Ordinal);
+        Assert.DoesNotContain("OFF · RELAY TIME", ux, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void Recovery_RestoresGoldenWpfVirtualizationAndForbidsRuntimeModeMutation()
+    {
+        var root = FindRepoRoot();
+        var xaml = File.ReadAllText(Path.Combine(root, "IoListTestingWindow.xaml"));
+
+        // The physical-bench failure proved that VirtualizationMode must never be mutated
+        // from Loaded/OnInitialized/runtime code. Restore the Build #1868 XAML-owned policy.
+        Assert.Contains("EnableRowVirtualization=\"True\"", xaml, StringComparison.Ordinal);
+        Assert.Contains("EnableColumnVirtualization=\"True\"", xaml, StringComparison.Ordinal);
+        Assert.Contains("VirtualizingPanel.IsVirtualizing=\"True\"", xaml, StringComparison.Ordinal);
+        Assert.Contains("VirtualizingPanel.VirtualizationMode=\"Recycling\"", xaml, StringComparison.Ordinal);
+
+        Assert.False(
+            File.Exists(Path.Combine(root, "IoListTestingWindow.FatScrollStability.cs")),
+            "Do not reintroduce a runtime FAT virtualization patch. WPF throws if VirtualizationMode is changed after the ItemsHost has entered Measure.");
+
+        foreach (var file in Directory.EnumerateFiles(root, "IoListTestingWindow*.cs", SearchOption.TopDirectoryOnly))
+        {
+            var source = File.ReadAllText(file);
+            Assert.DoesNotContain("VirtualizingPanel.SetVirtualizationMode", source, StringComparison.Ordinal);
+        }
+    }
+
+    [Fact]
+    public void Recovery_KeepsGoldenFatMembershipAndEngineeringReturnPath()
+    {
+        var fatUx = File.ReadAllText(FindRepoFile("IoListTestingWindow.FatV2Ux.cs"));
+        var fatModeSwitch = File.ReadAllText(FindRepoFile("IoListTestingWindow.WorkspaceModeSwitch.cs"));
+        var mainModeSwitch = File.ReadAllText(FindRepoFile("MainWindow.WorkspaceModeSwitch.cs"));
+        var sharedScl = File.ReadAllText(FindRepoFile("MainWindow.SharedSclWorkspace.cs"));
+        var fatHost = File.ReadAllText(FindRepoFile("MainWindow.IoTesting.cs"));
+
+        Assert.Contains("point.WorkspaceSelected", fatUx, StringComparison.Ordinal);
+        Assert.Contains("point.IsIncludedInFat", fatUx, StringComparison.Ordinal);
+
+        Assert.Contains("Engineering Workspace", fatModeSwitch, StringComparison.Ordinal);
+        Assert.Contains("Return to Engineering without unloading this FAT project", fatModeSwitch, StringComparison.Ordinal);
+        Assert.Contains("owner.ShowEngineeringWorkspaceFromFat(this)", fatModeSwitch, StringComparison.Ordinal);
+        Assert.Contains("Hide();", fatModeSwitch, StringComparison.Ordinal);
+
+        Assert.Contains("_loadedIoFatWindow", mainModeSwitch, StringComparison.Ordinal);
+        Assert.Contains("ShowLoadedIoFatWorkspace", mainModeSwitch, StringComparison.Ordinal);
+        Assert.Contains("CurrentEngineeringSclSourcePaths", mainModeSwitch, StringComparison.Ordinal);
+        Assert.Contains("OpenSclFatSourcesAsync(sharedSources, selectionMode: null)", mainModeSwitch, StringComparison.Ordinal);
+
+        Assert.Contains("_sharedSclSelectionAuthorityDeviceIds", sharedScl, StringComparison.Ordinal);
+        Assert.Contains("RegisterLoadedIoFatWindow(window)", fatHost, StringComparison.Ordinal);
+        Assert.DoesNotContain("window.ShowDialog();", fatHost, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void Recovery_DoesNotReintroducePerCellLiveValueAuthorityPatch()
+    {
+        var root = FindRepoRoot();
+        var forbiddenPath = Path.Combine(root, "IoListTestingWindow.LiveValueAuthority.cs");
+
+        Assert.False(
+            File.Exists(forbiddenPath),
+            "The per-cell LIVE VALUE authority patch is forbidden on the Build #1868 recovery branch because it can fan out UI-thread subscriptions and regress FAT lifecycle behavior.");
+    }
+
+    private static string FindRepoFile(string relativePath)
+        => Path.Combine(FindRepoRoot(), relativePath);
+
+    private static string FindRepoRoot()
+    {
+        DirectoryInfo? directory = new(AppContext.BaseDirectory);
+        while (directory != null)
+        {
+            if (File.Exists(Path.Combine(directory.FullName, "IoListTestingWindow.FatV2Ux.cs")))
+                return directory.FullName;
+            directory = directory.Parent;
+        }
+
+        throw new DirectoryNotFoundException(
+            $"Could not locate repository root from '{AppContext.BaseDirectory}'.");
+    }
+}
diff --git a/tests/ARSAS.Tests/OfflineDataSetSignalSelectionRegressionTests.cs b/tests/ARSAS.Tests/OfflineDataSetSignalSelectionRegressionTests.cs
index b9d397a6..03be0935 100644
--- a/tests/ARSAS.Tests/OfflineDataSetSignalSelectionRegressionTests.cs
+++ b/tests/ARSAS.Tests/OfflineDataSetSignalSelectionRegressionTests.cs
@@ -6,14 +6,18 @@ namespace ARSAS.Tests;
 public sealed class OfflineDataSetSignalSelectionRegressionTests
 {
     [Fact]
-    public void DeviceInventoryMerge_FallsBackToOfflineSclDesignModel()
+    public void DeviceInventoryMerge_PreservesOpenedSclAuthorityAcrossFastReconnect()
     {
         var source = File.ReadAllText(FindRepoFile("Services/Iec61850DataSetSignalInventoryService.cs"));
 
         Assert.Contains(
-            "device.LiveDiscoveryModel ?? device.SclWorkspace?.DesignModel",
+            "device.SclWorkspace?.DesignModel ?? device.LiveDiscoveryModel",
             source,
             StringComparison.Ordinal);
+        Assert.Contains(
+            "partial live discovery",
+            source,
+            StringComparison.OrdinalIgnoreCase);
         Assert.DoesNotContain(
             "if (device.LiveDiscoveryModel is null)\n            return EmptyResult();",
             source,
diff --git a/tests/ARSAS.Tests/P0LifecycleAndTotPfRegressionTests.cs b/tests/ARSAS.Tests/P0LifecycleAndTotPfRegressionTests.cs
index 3594d1ac..a82711b9 100644
--- a/tests/ARSAS.Tests/P0LifecycleAndTotPfRegressionTests.cs
+++ b/tests/ARSAS.Tests/P0LifecycleAndTotPfRegressionTests.cs
@@ -50,7 +50,10 @@ public void StaticReport_TotPf_UsesExactSemanticEngineAuthorityWithoutMmsFallbac
         var projection = Read("Services/StaticDataSetReportProjectionAccumulator.cs");
 
         Assert.Contains("\"sourcePullRequest\": 111", engineLock, StringComparison.Ordinal);
-        Assert.Contains("69bfe70e2c779c7e8268af087bd1a3a38986c0fc", engineLock, StringComparison.Ordinal);
+        Assert.Contains("0d7525bd330900917fb9f6d15a46059dc3d7a70a", engineLock, StringComparison.Ordinal);
+        Assert.Contains("P1 hardening", engineLock, StringComparison.Ordinal);
+        Assert.Contains("report-value position", engineLock, StringComparison.Ordinal);
+        Assert.Contains("omits MemberReference", engineLock, StringComparison.Ordinal);
         Assert.Contains("MmsSemanticReportValueProjector.Project", semanticBridge, StringComparison.Ordinal);
         Assert.Contains("session.StaticReportProjection.Project", runtime, StringComparison.Ordinal);
         Assert.Contains("MMS process fallback is disabled", runtime, StringComparison.Ordinal);
diff --git a/tests/ARSAS.Tests/StaticDataSetReportOnlyModeRegressionTests.cs b/tests/ARSAS.Tests/StaticDataSetReportOnlyModeRegressionTests.cs
index 50a41a62..0e9e804b 100644
--- a/tests/ARSAS.Tests/StaticDataSetReportOnlyModeRegressionTests.cs
+++ b/tests/ARSAS.Tests/StaticDataSetReportOnlyModeRegressionTests.cs
@@ -40,7 +40,7 @@ public void RuntimeContract_StaticDataSetMode_DoesNotScheduleCyclicMmsProcessPol
     }
 
     [Fact]
-    public void SharedSclStaticSelection_UsesExactAriecMembershipRows_NotEveryDatasetTaggedAlias()
+    public void SharedSclStaticSelection_UsesOnlyExactRcbBackedAriecMembershipRows()
     {
         var source = File.ReadAllText(FindRepoFile("MainWindow.SharedSclWorkspace.cs"));
         var authority = File.ReadAllText(FindRepoFile("Services/Iec61850StaticDataSetAuthoritySelection.cs"));
@@ -53,13 +53,62 @@ public void SharedSclStaticSelection_UsesExactAriecMembershipRows_NotEveryDatase
         Assert.DoesNotContain("UseStaticDataSetWithMmsFallback", source, StringComparison.Ordinal);
         Assert.DoesNotContain("fallback remains available", source, StringComparison.OrdinalIgnoreCase);
 
-        Assert.Contains("Iec61850DataSetSignalInventoryProjection.GetMandatorySignals(model)", authority, StringComparison.Ordinal);
+        Assert.Contains("var authorityModel = device.SclWorkspace?.DesignModel ?? device.LiveDiscoveryModel", authority, StringComparison.Ordinal);
+        Assert.Contains("Iec61850DataSetSignalInventoryProjection.GetMandatorySignals(authorityModel)", authority, StringComparison.Ordinal);
+        Assert.Contains("BuildReportBackedDataSetReferences(device)", authority, StringComparison.Ordinal);
+        Assert.Contains("reportBackedDataSets.Contains", authority, StringComparison.Ordinal);
+        Assert.Contains("var configurationModel = device.SclWorkspace?.DesignModel ?? device.LiveDiscoveryModel", authority, StringComparison.Ordinal);
+        Assert.Contains("AddReportBackedDataSets(configurationModel, result)", authority, StringComparison.Ordinal);
+        Assert.DoesNotContain("AddReportBackedDataSets(device.SclWorkspace?.DesignModel, result)", authority, StringComparison.Ordinal);
+        Assert.DoesNotContain("AddReportBackedDataSets(device.LiveDiscoveryModel, result)", authority, StringComparison.Ordinal);
         Assert.Contains("LiteralEquals(signal.DataSetReference, membership.DataSetReference)", authority, StringComparison.Ordinal);
         Assert.Contains("LiteralEquals(signal.DisplayReference, memberReference)", authority, StringComparison.Ordinal);
         Assert.DoesNotContain("StartsWith(memberReference", authority, StringComparison.Ordinal);
         Assert.DoesNotContain("Contains(memberReference", authority, StringComparison.Ordinal);
     }
 
+    [Theory]
+    [InlineData("IEDApplication/LLN0$BR$Buffer", "IEDApplication/LLN0$BR$Buffer01", true)]
+    [InlineData("IEDApplication/LLN0$BR$Buffer", "IEDApplication/LLN0$BR$Buffer02", true)]
+    [InlineData("IEDApplication/LLN0$BR$Buffer02", "IEDApplication/LLN0$BR$Buffer02", true)]
+    [InlineData("IEDApplication/LLN0$BR$Buffer02", "IEDApplication/LLN0$BR$Buffer01", false)]
+    [InlineData("IEDApplication/LLN0$BR$Buffer", "IEDApplication/LLN0$BR$Other01", false)]
+    [InlineData("IEDApplication/LLN0$BR$Buffer0", "IEDApplication/LLN0$BR$Buffer01", false)]
+    public void StaticRcbMatcher_AcceptsOnlyExactOrDecimalIndexedFamilyInstances(
+        string configured,
+        string live,
+        bool expected)
+    {
+        Assert.Equal(expected, Iec61850StaticRcbReferenceMatcher.IsConfiguredOrIndexedInstance(configured, live));
+    }
+
+    [Fact]
+    public void StaticRcbMatcher_ExactIdentityAlwaysRanksBeforeIndexedFamily()
+    {
+        const string configured = "IEDApplication/LLN0$BR$Buffer";
+        Assert.Equal(0, Iec61850StaticRcbReferenceMatcher.MatchRank(configured, configured));
+        Assert.Equal(1, Iec61850StaticRcbReferenceMatcher.MatchRank(configured, "IEDApplication/LLN0$BR$Buffer01"));
+        Assert.Equal(int.MaxValue, Iec61850StaticRcbReferenceMatcher.MatchRank(configured, "IEDApplication/LLN0$BR$Other01"));
+    }
+
+    [Fact]
+    public void DeterministicStaticPlanner_PreservesSclConfigurationAndConcreteLiveRcbAuthority()
+    {
+        var source = File.ReadAllText(FindRepoFile("Services/NativeIec61850Client.StaticDataSetReporting.cs"));
+
+        Assert.Contains("device.SclWorkspace?.DesignModel ?? device.LiveDiscoveryModel", source, StringComparison.Ordinal);
+        Assert.Contains("var configurationModel = projectionModel", source, StringComparison.Ordinal);
+        Assert.Contains("Iec61850StaticRcbReferenceMatcher.MatchRank", source, StringComparison.Ordinal);
+        Assert.Contains("SelectMany(configured => discovery.ReportInventory.ReportControls", source, StringComparison.Ordinal);
+        Assert.Contains("ReportControlReference = concreteReportReference", source, StringComparison.Ordinal);
+        Assert.Contains("Install InformationReport receiver before enabling the RCB", source, StringComparison.Ordinal);
+        Assert.Contains("Write RptEna=true, then request GI=true", source, StringComparison.Ordinal);
+        Assert.DoesNotContain("configurationModels", source, StringComparison.Ordinal);
+        Assert.DoesNotContain("var configured = configuredReports[0]", source, StringComparison.Ordinal);
+        Assert.DoesNotContain("AllowDynamicDataSetWrites = true", source, StringComparison.Ordinal);
+        Assert.DoesNotContain("PollingPointKeys = points.Select", source, StringComparison.Ordinal);
+    }
+
     [Fact]
     public void StaticDataSetRegressionGuard_PreservesFa16ReportOnlyDirection()
     {
@@ -103,8 +152,6 @@ public void SharedSclFat_IsConsumerOfExistingAcquisitionSession_NotASecondMonito
         Assert.Contains("if (!reuseSharedSclAcquisition)", source, StringComparison.Ordinal);
         Assert.Contains("Compatibility path for non-shared/legacy FAT only", source, StringComparison.Ordinal);
 
-        // The legacy helper may remain for workbook-only FAT, but the shared SCL branch
-        // must be structurally separate and must start through the normal Engineering owner.
         var sharedBranchStart = source.IndexOf("if (reuseSharedSclAcquisition)", StringComparison.Ordinal);
         var legacyBranchStart = source.IndexOf("Compatibility path for non-shared/legacy FAT only", StringComparison.Ordinal);
         Assert.True(sharedBranchStart >= 0 && legacyBranchStart > sharedBranchStart);