Vodafone UK has issued a text message warning to iPhone users on its network, blaming issues with 3G performance. In addition, The Next Web reviewed 27 pages of complaints on Apple's Support Communities forum, the first of which was logged on January 28.
Apple has not addressed the potential iOS 6.1 issue yet.
But one possible solution was offered by an iPhone user who visited an Apple Store genius (via The Next Web):
I went to see the genius’ yesterday. My problem was that my usage was almost identical to my stand by times, which means that something was continuing to run in the background after closing all the apps.
I was told to turn off location services and then one by one turn each in turn to see which one was causing the drain on the battery. I was impatient so just factory reset the handset which seems to have fixed the problem.
I’ll keep you all posted on how it continues.