It's very specific bug, that occurs in using QTableView when:

1. One use QTableView::openPersistentEditor
2. Rows number is big enough for QScrollArea to occur inside QTableView
3. One scroll till the very down, and step back on the half of line
4. One remove the last but one element.

Go to very bottom of TableView

Go up on half of line

Then delete the last but one element

And shift of editors occurs. If one resize the window or reopen all persistentEditors, it will become normal again. Example project in attach