For Xperia U on ICS
- No USB connection in recovery whatsoever (no adb, no USB mount etc.)
- No offline charging in recovery (for now, forgot a line of script)
Apart from the few issues above, everything else works! To get into recovery simply start your phone normally, and when you see the LED bar turn dark red, press the down button once. Your device will then enter recovery mode.
Flash using fastboot!