While the rest of the world already has access to the October 2021 security update, Galaxy S21 users in the USA might have to wait a wee bit longer. The US variants of the Galaxy S21, S21+, and S21 Ultra were updated with the September security patch late last month, and at least T-Mobile is now rolling out another update that doesn’t bump up the security patch version to the latest one.
However, while the previous update didn’t bring anything but security enhancements, the changelog for this one says that overall stability of the device has been improved. It’s not an exciting changelog, but it suggests Samsung and T-Mobile had a good reason to push out another update with the same security patch. Not that they need any reason other than the fact that they’re testing Android 12 and One UI 4.0 for Samsung’s latest Galaxy S flagships at the moment, but still.
In any case, the latest update for T-Mobile Galaxy S21 units comes with firmware version G99xUSQU4AUIL and can be downloaded over the air from the phone’s Settings » Software update menu. The relevant firmware is also available in our archive and can be used for manually upgrading using a Windows PC.