diff --git a/.repository-projection.json b/.repository-projection.json
index 40ab7b2..7ace0b6 100644
--- a/.repository-projection.json
+++ b/.repository-projection.json
@@ -3,11 +3,11 @@
   "projection": "borg",
   "projectionSchemaVersion": 1,
   "sourceRepository": "dx-corp/mono",
-  "sourceSha": "0cf84f90bfd2316c7942db9040adf02600a4185f",
+  "sourceSha": "957fcce869bc4aa2aeca09a23dcb933b23437704",
   "destinationRepository": "dx-corp/borg",
-  "priorProjectedBase": "d9fa852ceaab9c0d87678461edf39376ac996ab5",
+  "priorProjectedBase": "fca0fb4012d288364bc6dd8a20f28537f4829584",
   "definitionDigest": "78ba8d1b5794c261ff0afba6d99abc10b9297ea0dd94be4397fb1cbf63cf0c6e",
   "toolDigest": "3236c76d5bddbdab39d448c244f17fb36fa84e10",
-  "contentDigest": "017dbfc9a5add83f90bc00e037efe2247c8a235c22a751939922c8fa647ba96f",
+  "contentDigest": "1ea246ccf3856b94f5430e9bb5279ceb192487c91f7388bd972723fd097a3661",
   "publicationEligible": true
 }
diff --git a/src/janitor.rs b/src/janitor.rs
index 1873728..0cf4f27 100644
--- a/src/janitor.rs
+++ b/src/janitor.rs
@@ -11,7 +11,8 @@
 //! superseded runs that already started, and `dedupe_same_sha` cancels queued
 //! duplicates of a run of the same workflow, commit, event and pull request.
 //! Duplicate groups never include `workflow_dispatch` or `merge_group` runs,
-//! and a running duplicate is never cancelled. The
+//! and a running duplicate is never cancelled, even when its workflow still
+//! reads `queued`. An unreadable jobs response also preserves the run. The
 //! janitor is opt-in (`supersede_janitor` in the queen config). Cancelling
 //! runs needs `actions: write`: the janitor uses the queen's App installation
 //! token (minted and refreshed on demand) unless the config names a static
@@ -97,8 +98,8 @@ pub struct PassReport {
     /// Superseded push runs left alone because one of their jobs is running.
     /// GitHub shows a run as `queued` while any job waits for a runner.
     pub started_push: u32,
-    /// Runs that changed state between the listing and the cancel and were
-    /// left alone.
+    /// Runs left alone when a fresh status, head or active child job
+    /// contradicted the listing used to select them.
     pub raced: u32,
     /// Runs whose cancel GitHub answered with 409 (already finished, or stuck
     /// in a state GitHub will not cancel).
@@ -597,6 +598,19 @@ impl Janitor {
                     report.deferred += 1;
                     continue;
                 }
+                // A waiting sibling can keep the workflow queued after jobs start.
+                match self.has_running_job(repo, run.id).await {
+                    Ok(false) => {}
+                    Ok(true) => {
+                        report.raced += 1;
+                        continue;
+                    }
+                    Err(e) => {
+                        tracing::warn!("janitor: {repo} run {}: {e}", run.id);
+                        report.errors += 1;
+                        continue;
+                    }
+                }
                 let why = format!(
                     "duplicate of run {kept} (workflow {}, head {})",
                     run.workflow_id, run.head_sha
diff --git a/tests/janitor.rs b/tests/janitor.rs
index 8cc629a..2b4c59f 100644
--- a/tests/janitor.rs
+++ b/tests/janitor.rs
@@ -294,6 +294,64 @@ async fn queued_duplicates_keep_the_lowest_id() {
     assert_eq!(r.duplicates, 0, "{r:?}");
 }
 
+#[tokio::test]
+async fn a_queued_duplicate_with_a_running_job_is_kept() {
+    // GitHub's workflow stays queued while a sibling job waits for a runner.
+    // cancel_running must never opt same-head duplicate cleanup into killing it.
+    for cancel_running in [false, true] {
+        let h = Harness::start(with(json!({
+            "dedupe_same_sha": true, "cancel_running": cancel_running
+        })))
+        .await;
+        h.state().pulls.insert(10, "sha".into());
+        h.add_run(4, "queued", "pull_request", "sha", Some(10));
+        h.add_run(9, "queued", "pull_request", "sha", Some(10));
+        h.add_run_job(9, "active", "in_progress", Some("runner-1"));
+        h.add_run_job(9, "waiting", "queued", None);
+
+        let r = h.janitor_pass().await;
+        assert_eq!(
+            (r.duplicates, r.dedup_cancelled, r.errors, r.raced),
+            (1, 0, 0, 1),
+            "{r:?}"
+        );
+        assert!(h.state().cancelled.is_empty());
+    }
+}
+
+#[tokio::test]
+async fn an_unreadable_duplicate_job_response_preserves_the_run() {
+    let h = Harness::start(with(json!({"dedupe_same_sha": true}))).await;
+    h.state().pulls.insert(10, "sha".into());
+    h.add_run(4, "queued", "pull_request", "sha", Some(10));
+    h.add_run(9, "queued", "pull_request", "sha", Some(10));
+    // An invalid provider response cannot establish that no job is running.
+    h.state()
+        .jobs
+        .push(json!({"id": 90, "run_id": 9, "status": false}));
+
+    let r = h.janitor_pass().await;
+    assert_eq!((r.dedup_cancelled, r.errors), (0, 1), "{r:?}");
+    assert!(h.state().cancelled.is_empty());
+}
+
+#[tokio::test]
+async fn keeping_an_active_duplicate_leaves_the_cancel_budget_for_an_idle_one() {
+    let h = Harness::start(with(json!({
+        "dedupe_same_sha": true, "max_cancels_per_pass": 1
+    })))
+    .await;
+    h.state().pulls.insert(10, "sha".into());
+    for id in [4, 6, 9] {
+        h.add_run(id, "queued", "pull_request", "sha", Some(10));
+    }
+    h.add_run_job(6, "active", "in_progress", Some("runner-1"));
+
+    let r = h.janitor_pass().await;
+    assert_eq!((r.dedup_cancelled, r.deferred, r.raced), (1, 0, 1), "{r:?}");
+    assert_eq!(h.state().cancelled, [9]);
+}
+
 #[tokio::test]
 async fn a_running_duplicate_is_kept_and_never_cancelled() {
     let h = Harness::start(with(json!({"dedupe_same_sha": true}))).await;