diff --git a/.kiro/specs/scheduler-sim-step-verbosity/tasks.md b/.kiro/specs/scheduler-sim-step-verbosity/tasks.md
index 076b3430..4057b219 100644
--- a/.kiro/specs/scheduler-sim-step-verbosity/tasks.md
+++ b/.kiro/specs/scheduler-sim-step-verbosity/tasks.md
@@ -16,7 +16,7 @@
   - _Boundary: Event Echo Preamble Deduplicator_
 
 - [ ] 2. Validation: regression and real-transcript verification
-- [ ] 2.1 Verify every other REPL command and mode's existing behavior remain unchanged outside the preamble's own deduplication
+- [x] 2.1 Verify every other REPL command and mode's existing behavior remain unchanged outside the preamble's own deduplication
   - Confirm which events are echoed, event ordering, event content, and every other REPL command's behavior and output match their pre-feature baseline exactly except for the preamble line's now-conditional printing; confirm no scheduling decision or simulation state changed as a result of this feature
   - Observable: the existing REPL test suite's pre-existing assertions all still pass, updated only where a specific assertion pinned the old always-print-preamble shape for two events that legitimately share rendered context (each such update documented with which acceptance criterion justifies it), and a step-mode transcript comparison against the pre-feature baseline shows no textual difference outside the preamble line's presence or absence
   - _Requirements: 2.1, 2.3, 2.4_