T-Mobile US Xperia Z1s customers are still awaiting the Android 4.4.2 KitKat firmware update, despite the fact that the global Xperia Z1 has already received the update. Well judging by the latest PTCRB certification for the C6916 model number, it looks like it may roll in a matter of weeks. Firmware build 14.3.D.0.183 has been certified, which follows on from the last certified version with build 14.2.C.0.159 i.e. a move from 14.2.C.0.XXX to 14.3.D.0.XXX. If this new update does start to roll, we’ll keep you posted.