diff --git a/libs/sk_ps_discovery/src/lib.rs b/libs/sk_ps_discovery/src/lib.rs
index 80244ea246..069d411af9 100644
--- a/libs/sk_ps_discovery/src/lib.rs
+++ b/libs/sk_ps_discovery/src/lib.rs
@@ -20,7 +20,10 @@ pub struct World {
     attachments: BTreeMap<TenantShardAttachmentId, NodeId>,
 
     quiesced_timelines: BTreeMap<TenantTimelineId, Lsn>,
-
+    // ^
+    // either a timeline is in quiesced_timelines
+    // or it is in commit_lsns + remote_consistent_lsns
+    // v
     commit_lsns: BTreeMap<TenantTimelineId, Lsn>,
     remote_consistent_lsns: BTreeMap<TimelineAttachmentId, Lsn>,
 }
@@ -56,6 +59,9 @@ pub struct RemoteConsistentLsnAdv {
 
 impl World {
     fn check_invariants(&self) {
+        if !cfg!(debug_assertions) {
+            return;
+        }
         // quiescing
         {
             let quiesced_timelines: HashSet<TenantTimelineId> =
diff --git a/libs/sk_ps_discovery/src/tests.rs b/libs/sk_ps_discovery/src/tests.rs
index d021e0133f..df9c3e149e 100644
--- a/libs/sk_ps_discovery/src/tests.rs
+++ b/libs/sk_ps_discovery/src/tests.rs
@@ -160,6 +160,12 @@ fn quiescing_timeline_catchup() {
     });
     world.handle_commit_lsn_advancement(ttid, Lsn(23));
 
-    let advs = world.get_commit_lsn_advertisements();
-    validate_advertisements(advs, vec![(ps_id, vec![(ttid, Lsn(23))])]);
+    assert!(world.quiesced_timelines.is_empty());
+
+    world.handle_remote_consistent_lsn_advertisement(RemoteConsistentLsnAdv {
+        attachment: tenant_shard_attachment_id.timeline_attachment_id(timeline_id),
+        remote_consistent_lsn: Lsn(23),
+    });
+
+    assert!(world.quiesced_timelines.contains_key(&ttid));
 }