diff --git a/workplans/MAS-WP-0003-provider-live-test.md b/workplans/MAS-WP-0003-provider-live-test.md
index 8cf82d7..4c99a7c 100644
--- a/workplans/MAS-WP-0003-provider-live-test.md
+++ b/workplans/MAS-WP-0003-provider-live-test.md
@@ -121,6 +121,11 @@ address and what envelope recipient arrives.
   The result is identical to Gmail. All four addresses were accepted
   unquoted and arrived byte-identical, with the same classification and
   app statuses (201/202/202/202).
+- 2026-10-18, Outlook desktop client with the same Microsoft 365 account
+  (binect.de, subjects "Test 4.1-4.4", 08:57-08:59Z): mail was delivered by
+  Exchange Online from another pool (52.101.171.x). The result is
+  identical: all four addresses arrived byte-identical, with app statuses
+  201/202/202/202. The compose client makes no difference within M365.
   Still open: consumer Outlook.com (outlook.com/hotmail.com account), and
   the reply test (blocked: no outbound mail).