diff --git a/PLAN.md b/PLAN.md
index 5e05bb525ef5b42396e3b0e68482bd78e3e6c341..bf4074b103addc443880d948129f9d5bfa0cfddf 100644
--- a/PLAN.md
+++ b/PLAN.md
@@ -331,7 +331,7 @@
 preceding gate passes. If a feasibility gate fails, change the design before
 you continue the feature work.
 
-**Current milestone:** Milestone 6.4 — Limits and abuse resistance.
+**Current milestone:** Milestone 6.5 — Observability.
 Update this marker only after the current milestone gate passes.
 
 ### Architecture