Samsung and AT&T has just released the Android 4.1.2 Jelly Bean update for Samsung Galaxy S II Skyrocket (SGH-I727). AT&T seems can’t afford to be left behind after seeing T-Mobile’s pushed the Android 4.1.2 on their own Galaxy S II (SGH-T989). This update brings the new Android build version I727UCMC1 and packed with 4.1.2 Jelly Bean sweetness such Google Now with enhanced voice activation
Adds Browser bar, Drive Mode, ATT Locker, Mobile Hot Spot, Featured Apps widget as preloaded applications
Removes Qik and MSpot applications and Improved Call Quality.
Again, this update is now live via Samsung Kies, so just connect your Galaxy S2 into your computer and hit that Kies and hunt down this Android 4.1.2 Jelly Bean (I727UCMC1) software update.
Just make sure your device battery has enough charge and it should not rooted. If you root it before, you will lose root after the update.