diff --git a/packages/client-runtime/src/state/session.ts b/packages/client-runtime/src/state/session.ts
index 5787bd0e60b7..15848d95d965 100644
--- a/packages/client-runtime/src/state/session.ts
+++ b/packages/client-runtime/src/state/session.ts
@@ -30,8 +30,8 @@ function initialConfigOption<E>(
   );
 }
 
-// Bounded like the snapshot fetches: a wedged environment must not pin the
-// permissions check (and with it the settings UI) in a loading state for long.
+// Bounded so a wedged environment cannot pin the permissions check (and with it
+// the settings UI) in a loading state for long.
 const DEFAULT_SESSION_STATE_TIMEOUT_MS = 6_000;
 
 /**
diff --git a/packages/client-runtime/src/state/shellSnapshotHttp.ts b/packages/client-runtime/src/state/shellSnapshotHttp.ts
index 84ab1a3f1d4b..fe5a3d5fcec1 100644
--- a/packages/client-runtime/src/state/shellSnapshotHttp.ts
+++ b/packages/client-runtime/src/state/shellSnapshotHttp.ts
@@ -12,9 +12,13 @@ import { environmentEndpointUrl } from "../environment/endpoint.ts";
 import { ManagedRelayDpopSigner } from "../relay/managedRelay.ts";
 import { executeAuthenticatedEnvironmentHttpRequest } from "./environmentHttpAuth.ts";
 
-// Bounded so a pathologically slow endpoint cannot block the (cheaper) socket
-// fallback for long. The cached shell renders while this runs.
-const DEFAULT_SHELL_SNAPSHOT_TIMEOUT_MS = 6_000;
+// Long enough for a slow but alive server to finish. On timeout the socket asks
+// the same server for the same full snapshot, so a short deadline only throws
+// the first build away. The socket fallback is for setups where /api fails but
+// /ws works, such as a proxy that blocks /api. A dead server is caught by the
+// socket ping, which drops the session and interrupts this load. The cached
+// shell renders while this runs.
+const DEFAULT_SHELL_SNAPSHOT_TIMEOUT_MS = 20_000;
 
 /**
  * Load the environment shell snapshot (projects + thread shells) over HTTP
diff --git a/packages/client-runtime/src/state/threadSnapshotHttp.ts b/packages/client-runtime/src/state/threadSnapshotHttp.ts
index 9582ad30567b..da1156cc83e0 100644
--- a/packages/client-runtime/src/state/threadSnapshotHttp.ts
+++ b/packages/client-runtime/src/state/threadSnapshotHttp.ts
@@ -13,10 +13,13 @@ import { ManagedRelayDpopSigner } from "../relay/managedRelay.ts";
 import type { RemoteEnvironmentRequestError } from "../rpc/http.ts";
 import { executeAuthenticatedEnvironmentHttpRequest } from "./environmentHttpAuth.ts";
 
-// Bounded so a pathologically slow endpoint cannot block the (cheaper) socket
-// fallback for long. The cached thread renders while this runs, so the wait only
-// delays the transition to live data on the first open, not the initial paint.
-const DEFAULT_THREAD_SNAPSHOT_TIMEOUT_MS = 6_000;
+// Long enough for a slow but alive server to finish. On a cold open a timeout
+// makes the socket ask the same server for the same snapshot again, and older
+// turn pages have no fallback, so a short deadline only drops work. The socket
+// fallback is for setups where /api fails but /ws works, such as a proxy that
+// blocks /api. A dead server drops the socket session, which interrupts a
+// cold-open load. Older turn pages wait for this deadline.
+const DEFAULT_THREAD_SNAPSHOT_TIMEOUT_MS = 20_000;
 
 /**
  * Load a thread's detail snapshot over HTTP instead of embedding it in the