A
The short answer is that you can't. The long answer is that you can. Though, it requires reverting to a prior version of Android if there is a way to flash it onto your device. I'm not sure about Sony devices. But for Samsung and HTC, there are methods to flash factory images onto the devices reverting back to a particular version of Android. Not sure that it's the same for Sony devices.How to uninstall 4.4.2 on my Sony Xperia z