As the title suggests, last week I updated to ios 10.1 and my phone has started to shut down when battery is at 30-40%... I try to restart the phone and sometimes it works but then it shuts down again. It says that there is no battery left but the battery indicator keeps telling otherwise. Now I thought that it was just a matter of battery calibration. Which I did as per Apple's instructions like I have been doing all these years. So I did this but the phone keeps shutting down which makes me believe that there is juice in the battery after all and it is not a calibration issue. Anyone has any clue what I should be doing?