Uninstall application

Users can remove/uninstall a Github app from their repositories.
In thie scenario should we also delete all the backup data from our server?
I would suggest that we don't do this automatically as if a Github app is uninstall by mistake the user won't be able to recover their backup history. Instead we can maybe send an email to ask the users to confirm that they want to delete all their backups?
@nelsonic @iteles @Cleop do you have any ideas on this?