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@@ -199,9 +199,19 @@ _Split from the original S-09 — scoped to the portal only; the approval flow i
 
 ### S-10 · Document upload + boundary timer for document timeout (Flow 2)
 
-**Outcome:** BPMN extended with a "wacht op documenten" user task with a 30-day boundary timer. Self-service portal supports diploma upload. On timeout the case is cancelled.
+Split (issue #11 closed) into two independently-demoable slices per §13 — the original spanned six net-new surfaces including a new ZGW boundary:
 
-**Acceptance:** BDD scenarios for both branches; integration tests for the timer firing.
+#### S-10a · Document-wait task + 30-day timeout cancellation (workflow spine) — #102
+
+**Outcome:** BPMN gains a `WachtOpDocumenten` user task with a 30-day (P30D) interrupting boundary timer. On timeout the case is cancelled — the timer runs to a dedicated cancel end-event and the domain aggregate moves to a new terminal status via an external-worker (mirrors S-14 escalation / S-11 withdrawal). Backend only, no frontend.
+
+**Acceptance:** BDD both branches (documents-in-time vs timeout-cancel); live timer-fire via the management-API "move" idiom.
+
+#### S-10b · Diploma upload via ACL Documenten API + self-service portal — #103
+
+**Outcome:** the self-service portal supports diploma upload; the document is stored in the ZGW Documenten (DRC) API and related to the zaak, with all document calls routed through the ACL (§8.1). A successful upload completes the `WachtOpDocumenten` task from S-10a. Depends on #102.
+
+**Acceptance:** BDD upload-completes-wait-task; Playwright e2e upload journey.
 
 ### S-11 · Withdrawal (Flow 3)