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 6661a058..1b959339 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
@@ -521,3 +521,6 @@ names the principle that settles it, and is cited as "design 47 G A-n".
   through their views reader, and mesh-vault's two followers share its one writer.
 - **A-135** (corrects A-133(b); ADR 0595 §3; principle 7) The state template takes no cap: `digests` declares none and
   the template's fixed cap stands; §567's 4 MiB is the size expected, not a setting.
+- **A-136** (§483, §496; principle 1) The watchman's read of the build seats' steps goes, as §483 says: it times a
+  running ask from the build seat's step-progress event; its `reads seat:node-build-*.steps` and the holder lookup
+  for it go with it, and no holder event is needed.