10.5.1.A.0.283 firmware has been certified at PTCRB for Xperia Z, ZL, ZR and Tablet which is a higher build over previous 10.5.A.0.233 firmware update. Sony has already updated Xperia Z1 and Xperia Z Ultra on android 4.4.4 KitKat version while other Xperia “Z” series handsets are still on android 4.4.2.

10.5.1.A.0.283 firmware is believed to bring android 4.4.4 update for the time being but it can also be bug fixing update ( for the severe battery drain issue ).

[ UPDATE ] Xperia Z 10.5.1.A.0.283 firmware screenshot leaked – Android 4.4.4 update confirmed.

Xperia Z 10.5.1.A.0.283 firmware

Below you can see the 10.5.1.A.0.283 firmware certification for Xperia Z C6603, C6606 and C6616 on PTCRB.

Xperia ZL 10.5.1.A.0.283 firmware

Below you can see the 10.5.1.A.0.283 firmware certification for Xperia ZL C6502, C6503, C6506 PTCRB.

Xperia ZR 10.5.1.A.0.283 firmware

Below you can see the 10.5.1.A.0.283 firmware certification for Xperia ZR C5502,C5503 on PTCRB.

Xperia Tablet Z 10.5.1.A.0.283 firmware

Below you can see the 10.5.1.A.0.283 firmware certification for Xperia Tablet Z SGP321, SGP341, SGP351 on PTCRB.

We will keep you updated as soon as 10.5.1.A.0.283 firmware starts rolling for above mentioned Xperia handsets. Facing any bugs on present firmware, let us know. Drop your comments below.