diff --git a/NucleicRemote/NucleicRemote/Models/RemoteStore.swift b/NucleicRemote/NucleicRemote/Models/RemoteStore.swift
index 5d89059..ab110a0 100644
--- a/NucleicRemote/NucleicRemote/Models/RemoteStore.swift
+++ b/NucleicRemote/NucleicRemote/Models/RemoteStore.swift
@@ -691,15 +691,19 @@ final class RemoteStore: ObservableObject {
 
     func open(_ sessionID: SessionID) {
         openSessionID = sessionID
+        // Record which Mac owns this session (mesh P3) so its connection forwards the transcript and
+        // the host-specific projected values follow it.
+        openSessionHostID = connection(owningSession: sessionID)?.hostID
         openEvents = []
         openApprovals = []
         openDiff = nil
         diffLoading = false
         markOpened(sessionID)
         if demoMode { seedDemoTranscript(sessionID); return }
-        // The open transcript belongs to the active host; tell its connection so it forwards the
-        // snapshot/events (and dedupes them), then subscribe.
-        activeConnection?.openSessionID = sessionID
+        // Tell the owning connection so it forwards the snapshot/events (and dedupes them), re-derive
+        // the context host (capabilities/scope/catalog/connectivity now follow it), then subscribe.
+        connection(owningSession: sessionID)?.openSessionID = sessionID
+        rebuildAggregate()
         send(.subscribe(Subscribe(sessionID: sessionID, sinceSeq: nil, verbosity: .full)))
     }