Has anyone else seen this behavior on an iPhone 17 Pro Max running iOS 27? I set the charging limit to 80%, but the battery continued climbing to 86%. Later, while the phone wasn't connected to a charger, the displayed level suddenly jumped from 86% to 96%. Is this a bug, or is the charging limit expected to be ignored sometimes?
2 Answers
If you're using a beta release, unexpected battery behavior can happen. Beta software is still being tested, so it may be worth installing the latest update or returning to a stable release if the issue continues.
The charging limit can occasionally be exceeded, including charging all the way to 100%, so the phone can calibrate its battery-health and percentage estimates. That behavior isn't necessarily caused by the update. A jump from 86% to 96% while unplugged may simply be the system recalculating the estimate, especially if this only happened once.
This was the first time I noticed it. The bigger concern was that it jumped from 86% to 96% even though the phone wasn't connected to a charger.

I tried the beta mainly to test the new Siri and AI shortcut features, along with the improved image editing. The battery behavior is the part that caught me off guard.