T-Mobile appears to be doing well in terms of Galaxy S5 pre-registrations, however there is still something coming for current Galaxy S 4 users. The carrier has detailed the Kit Kat update, with mention of the rollout beginning today, March 10th. T-Mobile Galaxy S 4 users will be getting Android 4.4.2 and the update is available over-the-air and by way of Kies.
Along with the bump to version 4.4.2 Kit Kat, those who update will also see M919UVUFNB4 as the baseband. The update measures in at 388MB in size, and as we often see with T-Mobile handset updates -- they mention how your device cannot be rooted, and then suggest you begin the update process with a minimum of 50 percent battery life.
Also worth mentioning here, those going to the over-the-air route will need to be connected to WiFi. Otherwise, along with Kit Kat, this update is said to bring some stability improvements, some keyboard improvements, and users will also notice a new camera shortcut on the lockscreen.
Those looking to get the update should double check their battery, make sure they have a few minutes of time to let the update properly run the course, and then head into the settings. Specifically, you will want to head to Settings -> More -> About device -> Software Update to get the process started. Assuming the update is available for your specific device, from that point it is just a matter of following the prompts.