Edit UI: review name change scenarios

In response to #15685, Edit UI should be reviewed to ensure the correct data is being set and to make it clear in the code.

- [ ] review all name change scenarios
- [ ] review filing properties being set in each case
- [ ] add code comments, or some other mechanism, to make this all clear in the code
- [ ] create any new tickets to fix any bugs found along the way

Start from the Edit UI and trace each name-change scenario, checking which filing properties are set in each case. The work is done when the scenarios have been reviewed, the code clearly documents the behavior, and separate tickets are created for any bugs found.

Written by the indexing model from the issue text.