Updated models with AMD graphics options expected in early 2017.
Apple Studying Issue With iPhone 6s & 6s Plus Not Updating Battery Percentage
The company notes it is investigating the issue and working on a solution, although it appears to be related to time zone or clock settings. In the meantime, users experiencing the problem are advised to restart their devices and make sure the time is being automatically set in Settings.
If you change the time on your iPhone 6s or iPhone 6s Plus manually or change time zones when traveling, you might notice that the battery percentage doesn't update. Learn what to do.A fairly lengthy discussion thread in Apple's discussion forums reveals a number of users running into the problem, dating back nearly to the new models' launch last September. Many of the users experiencing the issue had been manually adjusting their phones' clock settings in order to bypass timer-based barriers in certain games, and Apple's suggestion about ensuring the time is being set automatically indicates the battery issue is indeed likely related to clock settings.