Some carriers in the United States have already released Android 5.0 for the Galaxy Note 4 but T-Mobile is not one of them, despite the fact that Magenta has already released the Lollipop update for the Galaxy Note 3. The carrier has not given an official release date for this update just yet but there has been a positive development today which hints that the release might not be that far off.
T-Mobile runs a software update tracker on its website which lets everybody see the status of upcoming updates. Previously the Galaxy Note 4 was listed under “manufacturer development,” which is carrier speak for a mere assurance that the update will be released at some point. Now though it's listed under “T-Mobile Testing,” which means that the carrier is putting the Lollipop update for this device through its paces to find out any potential issues before it's released to everybody. Usually this process doesn't take more than a couple of weeks, barring any issues that need fixing, so it appears that Galaxy Note 4 owners on T-Mobile might receive this update in the near future.