https://docs.bazzite.gg/Installing_and_Managing_Software/Updates_Rollbacks_and_Rebasing/rebase_guide/

This should answer most, if not all of your questions.

It’s important to remember, that you should rebase to the same DE to avoid issues. Although there shouldn’t be any data loss when rebasing, a backup of your files is recommended.

Edit: Forgot to write, that these principles apply to all atomic distros. But depending on the distro you’re using, the rebasing commands might be slightly different. So always look on the documentation of your distro.

Sounds interesting. Do you have a source for the mentioned research?