Another carrier has (surprisingly) beat AT&T to the punch for the Lumia Denim update. T-Mobile US is now pushing out the update to its small but dedicated base of Lumia 925 owners, bringing some new firmware and an OS upgrade.
T-Mobile themselves have not updated their support page, but Microsoft has, and tips from users tell us the update is live. Indeed, we have checked on two of our Lumia 925s for the US carriers and have updates waiting.
The OS update bumps users to version 14226 of the Windows Phone 8.1.1 updates, making it one of the latest releases of the OS for the public.
Likewise, the firmware is jumping from 1439 to 1451 (3051.50009.1451.0018), with what we presume are hardware optimizations for the venerable Lumia 925.
Unfortunately, Lumia Denim is not expected to bring many new hardware features like Lumia Camera 5.0, but support for folders, Cortana and more through the OS should be a welcome addition.
Windows Central will update this article as soon as T-Mobile posts a more detailed changelog. Meanwhile, we are going to upgrade our phones and advise you do the same.
Update: T-Mobile has now refreshed their support page, reflecting today's update. Unfortunately, the most they say about the new firmware change is "Stability improvements".
Jump into our Lumia 925 forums for help or questions!
Thanks, Ronaldo T., for the tip!