This was mentioned the other day too - Sidebar question about Admins configuring defaults for visitors and new members
I gave it a run-through and it seemed to work okay on my test site, and I’ve not been able to repro it so far to track it down further.
As the background jobs can take a while to run for everyone, it’s set up to change admin and anon first I think. If you have a lot of users it may take a while for the changes to work their way through everyone. ()