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 ade67fd7..9f7cb4ae 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
@@ -68,3 +68,6 @@ names the principle that settles it, and is cited as "design 47 G A-n".
 - **A-17** (§461, A-16; principle 7) `findings-asked` is always the seat `mesh-conditions`' event, so the writer names it
   with that seat, `mesh-conditions.findings-asked`, as a constant of mesh-sdk, in Go and TypeScript alike; no module
   supplies it.
+- **A-18** (§587, §305; principle 7) What G retires leaves no trace: the gate's record type drops the `remove` operation
+  and `OpRemove` (§587: a removal is no operation), and its `table`, `recheck` and `close` go with their handlers and
+  tools (§305). `checks`, which no line retires, stays.