diff --git a/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md b/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md
index f47adfcf..c49257a8 100644
--- a/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md
+++ b/03-DESIGN/01-to-be/47-milestones/G-20-lead-answers.md
@@ -291,3 +291,6 @@ names the principle that settles it, and is cited as "design 47 G A-n".
   (`versions.Source` gains it), so publish again reads that entry; the registry seat for an artifact is found from its
   package ecosystem as the builder's seat hearing already maps it. A transport fault's class (`no responders`, `name
   lookup`, `connection`, `deadline`) is the one the existing retake reads from the call's error (ADR 0664, ADR 0668).
+- **A-77** (§373; principles 1 and 7) A wait's bound is a bound key with its own time to live in the waiting part's own
+  state, as the condition keeper times its two hours (COND7): its expiry is heard as the bus's event and ends the wait
+  then, failing the step naming the member; no timer in the process and no looking only at the next event.