diff --git a/tests/Server/ZB.MOM.WW.OtOpcUa.Host.IntegrationTests/SecretsReplicationRegistrationTests.cs b/tests/Server/ZB.MOM.WW.OtOpcUa.Host.IntegrationTests/SecretsReplicationRegistrationTests.cs
index 974dadba..cbaee73c 100644
--- a/tests/Server/ZB.MOM.WW.OtOpcUa.Host.IntegrationTests/SecretsReplicationRegistrationTests.cs
+++ b/tests/Server/ZB.MOM.WW.OtOpcUa.Host.IntegrationTests/SecretsReplicationRegistrationTests.cs
@@ -106,11 +106,20 @@ public sealed class SecretsReplicationRegistrationTests
         // Asserted on the ServiceCollection rather than a built provider, deliberately. Resolving
         // ISecretStore with replication on constructs ReplicatingSecretStore, which resolves
         // ISecretReplicator, which eagerly spawns the replication actor, whose PreStart calls
-        // DistributedPubSub.Get(...). That needs a joined cluster, so a provider-based assertion
-        // HANGS here rather than failing. Standing a real cluster up inside this assembly was
-        // attempted and does not work; the library's own TwoNodeClusterReplicationTests already
-        // cover actor creation and convergence against a genuine 2-node cluster, so duplicating
-        // that here buys nothing.
+        // DistributedPubSub.Get(...) — unavailable until the node has joined a cluster. Against a
+        // plain ActorSystem that resolve hangs instead of failing.
+        //
+        // Akka.TestKit is the family convention for this (ScadaBridge's suites use it throughout)
+        // and would be the right tool, but it is NOT available here: Akka.TestKit.Xunit2 is
+        // xunit-v2-only, and this project is one of the 44 on xunit.v3. Adding it yields CS0433
+        // type conflicts. Directory.Packages.props documents the same constraint — AdminUI.Tests,
+        // ControlPlane.Tests and Runtime.Tests are deliberately held on xunit v2 precisely because
+        // no xunit.v3 TestKit ships as of Akka 1.5.62. Host wiring tests belong here, not in one of
+        // those three, so the descriptor is the right seam until Akka ships a v3 TestKit.
+        //
+        // Nothing is lost: the registration order IS the defect, and the library's own
+        // TwoNodeClusterReplicationTests already cover actor creation and convergence against a
+        // genuine 2-node cluster.
         //
         // AddSingleton (not TryAdd) appends the decorator, and the LAST registration for a service
         // type is what the container resolves.