Steps to reproduce:

1. Create 5 folders under Ibexa Digital Experience Platform directory.
2. Add Content Scheduler block.
3. Set limit to 3 items.
4. Pick 5 newly created folders and leave the current date.
5. Click "Submit".
6. Delete first item that is shown in the Content Scheduler block using Content Tree.
7. Edit the Landing Page with Content Scheduler block.
8. You can see 2 items instead of 3 - one has been removed but is still visible in Content Scheduler block form - this is correct behavior but it could be improved.

Expected result:
The deleted content should be replaced by one of the two remaining contents so one could still see 3 items instead of 2 according to the limit set.