diff --git a/NucleicRemote/NucleicRemote/Views/SessionDetailView.swift b/NucleicRemote/NucleicRemote/Views/SessionDetailView.swift
index d431fad..5617f14 100644
--- a/NucleicRemote/NucleicRemote/Views/SessionDetailView.swift
+++ b/NucleicRemote/NucleicRemote/Views/SessionDetailView.swift
@@ -408,14 +408,24 @@ struct SessionDetailView: View {
                         // than being sent and silently ignored.
                         set: { on in if on { store.setSessionOrchestra(sessionID) } }),
                     catalog: store.intelligenceCatalog,
-                    enabled: store.connectivity.isLive && !summary.archived,
+                    // Locked once the chat is in Orchestra, matching the Mac's composer: from
+                    // there its model is the supervisor configured on the host, not a stop on
+                    // this rail, and the host refuses a level for it anyway
+                    // (`setSessionIntelligence`) — so the rail parks on the node rather than
+                    // offering moves that would bounce.
+                    enabled: store.connectivity.isLive && !summary.archived && !sessionOrchestra,
                     // Always offered — no Nucleic Control gate. See the new-chat composer.
                     orchestraAvailable: store.intelligenceCatalog.orchestraAvailable,
                     composerText: draft,
                     routeDescription: sessionRouteDescription,
                     unavailableReason: summary.archived
                         ? "This chat is archived."
-                        : (store.connectivity.isLive ? nil : "The Mac that owns this chat is offline."),
+                        : !store.connectivity.isLive
+                            ? "The Mac that owns this chat is offline."
+                            : (sessionOrchestra
+                                ? "This chat runs Orchestra — its supervisor model is set on the "
+                                    + "Mac and stays fixed for the life of the chat."
+                                : nil),
                     onPreviewChanged: { intelligencePreview = $0 })
                 IntelligenceRouteLine(
                     level: level,