Message from Microsoft:
Message ID: MC299922
Published: 24 November 2021
We'll be making some changes to Teams Direct Routing.
Note: Starting on January 3, 2022, Direct Routing will stop processing SIP requests which have Replaces headers.
When will this happen:
We will begin this change in early January '22 and expect to complete mid-January '22.
How this will affect your organization:
When this change is implemented, Direct Routing will reject SIP requests that have Replaces headers defined.
What you need to do to prepare:
Please check your Session Border Controller configuration and be sure that you are not using Replaces headers in SIP requests.
• Configure Direct Routing: https://docs.microsoft.com/en-us/microsoftteams/direct-routing-configure
You can also view this message in the Microsoft 365 admin center.