diff --git a/apps/pwa/src/components/EventForm.tsx b/apps/pwa/src/components/EventForm.tsx
index d3bf3d8..10a99ab 100644
--- a/apps/pwa/src/components/EventForm.tsx
+++ b/apps/pwa/src/components/EventForm.tsx
@@ -352,8 +352,18 @@ export function EventForm() {
     if (recurrence !== 'none') {
       if (recurrenceBound === 'count' && recurrenceCount < 1) {
         newErrors.recurrenceBound = 'Must be at least 1 occurrence'
-      } else if (recurrenceBound === 'until' && recurrenceUntil) {
-        if (recurrenceUntil < startDate) {
+      } else if (recurrenceBound === 'until') {
+        // WR-02: a blank end date with bound='until' must be a validation error.
+        // Previously it passed validation and the payload spread dropped
+        // recurrenceUntil, silently creating an UNBOUNDED series — the opposite
+        // of the user's stated "Ends: On date" intent.
+        if (!recurrenceUntil) {
+          newErrors.recurrenceBound = 'Choose an end date'
+        } else if (startDate && recurrenceUntil < startDate) {
+          // WR-07: only compare when startDate is non-empty. Both values are
+          // zero-padded ISO DATE strings here, so lexicographic compare is valid;
+          // guarding on a non-empty startDate avoids `recurrenceUntil < ''` (always
+          // false) silently skipping the bound-before-start guard.
           newErrors.recurrenceBound = 'End date must be after the event starts'
         }
       }