Please see Update on Transport Enforcement System in Exchange Online for an updated timeline.
2/20/2025: Please note that thottling/blocking has now been enabled for all versions of Exchange Server...
Updated Feb 20, 2025
Version 8.0
Blog Post
10 MIN READ
Throttling and Blocking Email from Persistently Vulnerable Exchange Servers to Exchange Online
I have updated my Exchange Server 2016 to the latest SU build 5.1.2507.39 yet O365 is still detecting CU 5.1.2507.6. This is an issue on Microsoft's side and Microsoft need to find a better way of detecting build versions. How do we remedy this as I had to enforce pause for 90 days so that our emails doesn't get throttled and blocked? I have opened a ticket with Microsoft to ask how they will remedy this issue on their side.
Up-to-date build:
O365 report still detects build 15.1.2507.6:
Microsoft's patch/hotfix team is aware of Exchange Server build versions doesn't show SU build but the latest CU so then why isn't O365's team aware of this?
EDIT: It's resolved now. It takes 24 hours from time of update for O365 to detect the new build.