I accidentally upgrade and now I have lost the ability to switch back to the EDGE network. Earlier I had the option of EDGE and 3G. 3G speeds are not very good here in India and also call drops are frequent which is why I'm on EDGE all the time. When I need speed I switch to 3G but otherwise its EDGE. Now with the update, I have only 3G or LTE and its just killing the battery and also the call drops are too frequent. Somebody please tell me how I can downgrade my carrier settings.