Forum Discussion
Security Defaults Allows Setting Up SMS
I'm not sure what the experience will be, as i've not been in the position you are in. However, I would imagine that what you suspect will be what occurs after 14 days. Can't be sure though. You just never can tell for sure sometimes with Microsoft.
What I would say is that it's far more preferable in my opinion to control these settings yourself if you can. IE, turn off the security defaults in favour of deploying your own Conditional Access Policies and doing things like blocking legacy authentication. This will allow you to test at your own pace, enable CA policies to pilot users/groups, and run in reporting mode etc. Far better way in my opinion. Security defaults in theory are a good idea, but some organisations could get into trouble with them if they suddenly find blanket settings applied.