@harryz A way to migrate the data is:
Create a backup of the app
Install a new app instance with Cloudron user management
Import the backup into new instance . https://docs.cloudron.io/backups/#import-app-backup
Please double, no triple check the user management setup after import. The reason we don't have an easy way to change the SSO is because each app acts very differently when moving auth providers. Especially creation of default accounts, admin accounts, registration etc is all very app specific.