I simply wanted to know if there is any way to go back to the official 4.1.2 (i.e. as it was before the update to 4.3). I have not rooted the phone or done anything else with my phone. I have read all the stuff about Knox which I believe could prevent the phone to be downgraded without voiding the warranty, but this is not really a big issue for me as I've had the phone for over a year now. I was not ever planning on rooting the phone or adding any custom roms either. Just looking for a way to restore the phone as it was really!!
Hope anyone can help, and advance apologies for what is probably a very nooob question.
edited to add: I am on T-mobile (EE) in the UK, as I understand that AT-T cannot downgrade without bricking the phone.