Do not use an MDM through Apple Business Manager ever!

What no one tells you until too late is that the MDM actually embeds itself into the iCloud backup. So if anyone ever uses a MDM on a personal iCloud account, that MDM will be embedded in there forever.

There is no way to remove it without either restoring to a backup from prior to having the MDM or completely starting from scratch with all your Apps and Data.

What a redundant exercise.

This has caused me no end of trouble with staff members and my children.

Avoid at all costs unless Apple comes up with a solution that actually works.