You're not wrong. --- But I think it is still fun to guess and watching Microsoft's bug reports is a bit depressing since often M$ is never quick to resolve.
For those questioning RTM status... 16291 is not RTM. I've clean installed 16291 from a UUP Iso on a fresh VM and it's still enforcing Windows Insider settings even after setting it up with just a local user account.
- Stop the Windows Update service - Rename the "C:\Windows\SoftwareDistribution" to something else (e.g. SoftwareDistributionOLD) - Restart the Windows Update service (this will recreate a SoftwareDistribution folder in the C:\Windows directory) - Delete the "renamed" SoftwareDistribution folder - Delete the hidden folder "C:\$Windows.BT" folder if it exists - Run a Windows Update check again