diff --git a/discourse-release/announce.sh b/discourse-release/announce.sh
index fd46007..4ad8683 100755
--- a/discourse-release/announce.sh
+++ b/discourse-release/announce.sh
@@ -53,10 +53,19 @@ payload=$(jq -n --arg repo "$REPO" --argjson category "$category_id" --arg ext "
       )
     }')
 
-status=$(curl -sS -o /tmp/discourse-release.out -w '%{http_code}' -X POST "$FORUM/posts.json" \
-  -H "Api-Key: $API_KEY" -H "Api-Username: release-bot" \
-  -H "Content-Type: application/json" --data-binary "$payload")
-body=$(cat /tmp/discourse-release.out)
+# Two releases published together (a repo's main and its maintenance branch)
+# hit the forum's rate limit: Discourse answers 429 with how long to wait.
+# Wait that long (60 s at most) and try again, three times in all.
+for attempt in 1 2 3; do
+  status=$(curl -sS -o /tmp/discourse-release.out -w '%{http_code}' -X POST "$FORUM/posts.json" \
+    -H "Api-Key: $API_KEY" -H "Api-Username: release-bot" \
+    -H "Content-Type: application/json" --data-binary "$payload")
+  body=$(cat /tmp/discourse-release.out)
+  [ "$status" = 429 ] && [ "$attempt" -lt 3 ] || break
+  delay=$(jq -r '(.extras.wait_seconds // 15) | if type == "number" then . else 15 end | if . > 60 then 60 else . end | ceil' <<<"$body" 2>/dev/null || echo 15)
+  echo "forum rate limit; trying again in $((delay + 1)) s"
+  sleep $((delay + 1))
+done
 case "$status" in
   200)
     url="$FORUM/t/$(jq -r '.topic_slug' <<<"$body")/$(jq -r '.topic_id' <<<"$body")"