Update: Users who have tried to update their handsets using the Australian customisation number in build.prop, have ended up re-downloading Android 4.1.2. This could be a premature release from Sony, which was subsequently pulled. Assume that is the case until we have evidence of someone actually downloading and installing this update.
Update 2: Ignore us, it’s real check out the screenshot below. For more pictures click here.
Update 3: The FTF firmware file can be downloaded from here. [Thanks DooM!]
Thanks levered!