It’s possible but not particularly easy. The current way to do it would be through the backup/restore mechanism, effectively getting a backup, altering the state.txt to remove the registration and then restoring that onto the server.
Given it’s possible to do through backup/restore, I don’t really see a reason not to relax the API for this. Feel free to file an issue at Sign in to GitHub · GitHub and we can relax some of the checks around that.