PSA: There's a Graph API opt-out for the Sept 1 passkey auto-enrollment nudges....not in the email Microsoft sent, only in the FAQ
If you got the email about Microsoft retiring SMS/voice MFA, you probably only caught two dates:
Sept 1, 2026 — Entra auto-enables passkey registration nudges for anyone currently on SMS/voice
Feb 1, 2027 — Microsoft-provided SMS/voice is fully retired, no exceptions
What the email doesn't call out: there's a temporary opt-out for the Sept 1 part. It won't move your Feb 2027 deadline but it stops Microsoft from flipping on the registration campaign and hitting your end users with "set up a passkey now" nudges before you're actually ready to manage that rollout yourselves.
https://learn.microsoft.com/en-us/entra/identity/authentication/concept-sms-voice-retirement-faq
Go to the FAQ and read the section "What if I have different plans for my tenant than enabling passkeys for SMS/voice users (such as configuring a customer configured telecom provider or migrating users to another authentication method)?"
It will show you what you need to do to opt out.
It saved me so much anxiety and stress knowing we have more time to properly roll this out and not have our end users in a frenzy when the notification would have dropped.