diff --git a/.agents/skills/lib_py/delegation/wrapper.py b/.agents/skills/lib_py/delegation/wrapper.py
index 7051e46..4f5a589 100644
--- a/.agents/skills/lib_py/delegation/wrapper.py
+++ b/.agents/skills/lib_py/delegation/wrapper.py
@@ -143,11 +143,14 @@ def _check_owner(a: argparse.Namespace) -> None:
 
 
 def _sleep(a: argparse.Namespace, seconds: float) -> None:
-    """time.sleep that looks at the wrapper every 0.5 s."""
-    end = time.time() + seconds
+    """time.sleep that looks at the wrapper every 0.5 s. The span is measured
+    on the monotonic clock, as bash's `sleep N` is: a wall clock stepped back
+    during the wait must not stretch it (review R1, codex). Deadlines stay on
+    the wall clock (_now)."""
+    end = time.monotonic() + seconds
     while True:
         _check_owner(a)
-        left = end - time.time()
+        left = end - time.monotonic()
         if left <= 0:
             return
         time.sleep(min(left, 0.5))
diff --git a/tests/test_issue17_item4_decisions.py b/tests/test_issue17_item4_decisions.py
index fdd68e2..5580f99 100644
--- a/tests/test_issue17_item4_decisions.py
+++ b/tests/test_issue17_item4_decisions.py
@@ -591,3 +591,40 @@ def test_c_an_unreaped_wrapper_leaves_the_real_record_alone(tmp_path):
         time.sleep(6)
         states.append((rc, took < 4.5, json.loads((reg / f"{jid}.json").read_text())["status"]))
     assert states[0] == states[1] == (-15, True, "pending"), states
+
+
+# --- review R1 (codex): a wall clock stepped back does not stretch a wait ----
+
+class _SteppedClock:
+    """A `time` stand-in: wall and monotonic both advance on sleep(), and the
+    wall clock is stepped back once, during the first sleep."""
+
+    def __init__(self, step_back: float):
+        self.wall, self.mono, self.step_back, self.slept = 1000.0, 50.0, step_back, 0.0
+
+    def time(self):
+        return self.wall
+
+    def monotonic(self):
+        return self.mono
+
+    def sleep(self, dt):
+        self.wall += dt
+        self.mono += dt
+        self.slept += dt
+        if self.step_back:
+            self.wall -= self.step_back
+            self.step_back = 0
+
+
+@pytest.mark.parametrize("seconds", [1, 3])
+def test_u_a_wait_is_not_stretched_by_a_wall_clock_step_back(monkeypatch, seconds):
+    """The broker re-observation (up to 3 s) and the disk-heartbeat grace (1 s)
+    re-read the record after `seconds`, as bash's `sleep N` did, even when the
+    wall clock steps back 10 s meanwhile (on the old wall-clock arithmetic the
+    wait became seconds + 10)."""
+    import argparse
+    clock = _SteppedClock(step_back=10)
+    monkeypatch.setattr(decide, "time", clock)
+    decide._sleep(argparse.Namespace(watch_pid=None), seconds)
+    assert seconds <= clock.slept <= seconds + 0.5, clock.slept