Xperia SP won't start after update.

[iAmitp]

Xperia SP won't start after update.

[Uliwooly]

Connect your phone to the wall charger > press and hold power & volume up for 8 seconds > let it charge for 1 hour > after 1 hour try to turn it on 

[TK]

I have the same problem, the phone when charging cycles from green charge to red start with the sony logo then back to green. It filed the updated today (turned off during update)