Content item disappears from Full list after changing airtime.

Steps:
1. Create a new Landing page.
2. Add a Schedule block (hero).
3. Add content item A.
4. Add content item B.
5. Add content item A.
6. Add content item C.
7. Add content item A.
8. Check Full list. [screenshot 1]
9. Change airtime. [screenshot 2]
10. Check Full list. [screenshot 3]
Issue: The last item disappears from the list (also from timeline).

Remarks: On version 1.3.1 content item disappears after step 5 so the behaviour is different.