I know this is an old thread, but just in case someone stumbles across it, I wanted to share my experience.
It is possible to change the URL to a SharePoint list that is customized with a Power App by using PowerShell.
Changing the URL to the list will not delete your power app. However, I can not in good faith advise you that doing this is a good idea. The app will reappear after you give it a few minutes to sync, but it's still going to be using the old list as its datasource. Doing a Find and Replace in Power Apps to update all of the data connections will help, and any columns that existed prior to the name/url change will work just fine... That said, any new columns you add will not behave how you expect them to.
You will be able to add new columns and populate them with the app, but they will display as blank anytime you use the app to view an item, regardless of whether the column has data in it or not.
I've been at this for about 14 hours now, and will be publishing my new app version with the caveat that any data submitted in these columns will be added to the list, but will not be viewable via the app...
Plan moving forward: Make **bleep** sure that whatever we're naming the list when we create it, is EXACTLY what we want the name to be forever...
