Thank you for your post!
I understand that you want to disable some of the per-user MFA phone options and are looking to only apply these options to a Test group and not your entire organization. Unfortunately, when it comes to per-user MFA users are enabled individually, and if you want to apply your MFA options to a single Azure AD group, you'll have to leverage Conditional Access Policies.
Please note that enabling Azure AD MFA using Conditional Access policies is the recommended approach to protect users. Additionally, in March 2023, we announced the deprecation of managing authentication methods in the legacy multifactor authentication (MFA) and self-service password reset (SSPR) policies. For more info.
Additional Links:
- Migration between policies
- How policies work together
- Create a Conditional Access Policy - Prerequisites
- Features and licenses for Azure AD Multi-Factor Authentication
I hope this helps!
If you have any other questions, please let me know. Thank you for your time and patience throughout this issue.
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