The official Android 4.3 update for those who got the T-Mobile’s Galaxy S3 LTE version with model number (T999L). The update comes in new baseband version T999LUVUBMK4 and much likely brings similar features found on the non-LTE Galaxy S3 (T999) 4.3 released. The two main features of the 4.3 update are the Samsung Galaxy Gear and KNOX support, but there are also numerous improvements, including camera, keyboard, widgets and more. This update is now live and can be downloaded through over-the-air (OTA) from which bumps the device software build to 4.3 T999LUVUBMK4 from old build 4.1.2 T999LUVAMB7. The rolled-out was started on December 09, 2013 (yes we’ve missed-it since too many devices receiving 4.3 update recently) but still live until now since OTA update usually runs in weeks.
So for those who did not see this update yet, you may now hit your Device Settings>>About Phone>>Check for Update. Your phone must be fully re-charge and not rooted so you’ll get this update without facing update failure through OTA. If you’ve already received the update, have your say how this 4.3 performs on your Galaxy S3 T999L.
[Thank’s to XDA-Developers fellas for bringing this in]