Depends on D20006. Ref T13222. Currently, the "MFA Is Required" gate doesn't let you do anything else, but you'll need to be able to access "Contact Numbers" if an install provides SMS MFA.

Tweak this UI to give users limited access to settings, so they can set up contact numbers and change their language.

(This is a little bit fiddly, and I'm doing it early on partly so it can get more testing as these changes move forward.)