After a teaser today morning Android 4.2.2 for the Sony Xperia Z has been leaked, please note this is for Xperia Z models C6603 and C6602 only. Please do not flash this on any other Xperia Z model or Xperia ZL or the Xperia tablet. Also, you need to have an unlocked bootloader to install the leak.
This is a leaked build so do not expect it to be perfect but it’s good enough to quench your Dashclock thirst. Sony firmware version of the same is 10.3.A.0.407.
For more details, download links & instructions head over to the original thread at xda.