Most than likely MS boned up the existing registration.
That would have been ideal, but unfortunately program was still registered.
I'm holding off on any Win10 updates for now
Being an insider for over 2 years, you are right. This anniversary release is not ready for prime time. There have been 3 accumulative updates since release 14393 on the fast ring, and that was the iso image ms used when they released it. So one installs it, and right away you do 1 more accumulative update to 14393.10.
Just sucked putting it on my main machine. Even Disk Cleanup run as administrator did not clean out the windows.old directory. Had to manually go in and change permissions in order to get rid of that folder.