Come October 2022, anybody using an Outlook calendar with FreePBX will face issues where the calendar stops syncing which could inadvertently prevent Time Conditions/ Find Me Follow Me modules from working/ matching based off a calendar function.
Currently FreePBX only supports basic authentication for Office 365 logins.
Whilst this is not an issue yet, in October 2022 Microsoft will be disabling basic auth for all tenants with the exception of SMTP Auth.
This can be found in the following article:
Would it be possible to upgrade the PBX to support modern authentication methods in 365 so that it can tie the PBX with a Microsoft tenant ID/ client ID/ API Permissions and a secret?