Xperia Blog submitted a new resource: Xperia Z1s_C6916_14.5.B.0.236_US_T-Mobile - Sony Xperia Z1s (C6916) Android 5.0.2 firmware - T-Mobile US Read more about this resource...
http://www.xperiablog.net/2015/03/1...peria-lollipop-using-xperifirm-and-flashtool/ - Open link above and skip to the section entitled “FlashTool steps”. - As you have already downloaded the FTF firmware file, skip to the section where you need to “Flash device”.