Update went fine...but now my battery life is horrid. I'm talking a significant drop in battery at night while it's in Airplane mode. (I switch Airplane mode on if it isn't on charger at night.) Last night it dropped nearly 25% overnight...From about 79% to 57% It's confusing because there shouldn't be anything happening while in Airplane mode, right? I just repaired with my phone, but if that doesn't fix it is there any known way to downgrade to 3.1?