Share your experience!
Right now i had Android v4.0.4 in my sony xperia u. How can i to revert back to android v2.3
You have two options
1. Take your device to a service centre.
2.Flash your device.
If you opt for the 2nd solution
How to manually update, downgrade, root 2012 Xperias
http://talk.sonymobile.com/thread/41609
Don't forget to give Kudos
how to flash ??
All the info is on that link