In the page edit view it is not possible to set a block as the last element once the site is published.

Example / Steps to reproduce:
1. Create a landing page object
2. Place 3 - 5 Blocks (Text blocks for example).
3. Publish
4. Edit and go back to the block edit page view
3. Try to place/drag the first block on the last position at the bottom of the page
4. Publish
5. View the page or go back to the page edit, the block moved to the bottom will be placed as forelast element, not as the last/bottom element.

Expected result after sorting:
Sort order: 1. Textblock-2
Sort order: 2. Textblock-3
Sort order: 3. Textblock-4
Sort order: 4. Textblock-5
Sort order: 5. Textblock-1

Current result:
Sort order: 1. Textblock-2
Sort order: 2. Textblock-3
Sort order: 3. Textblock-4
Sort order: 4. Textblock-1
Sort order: 5. Textblock-5