Weird Battery Issue - HELP!

Since yesterday my battery % is all over the place. I take it off the charger in the AM and it is at 100%. I don't even touch it for like 20 min and it is at 87%, then it drops to like 62%. I do a reboot and it goes back to 94%. Then I use it for a few hours it drops to 42% and then stays there for hours of use never moving.

I called Apple Support and they did a battery diagnostic and said my battery is fine, and that this situation is, "weird". Yes, "weird"....duh! I can't get into an Apple Store until next week.

I have also done a settings reset......didn't help. And then I did a full iTunes restore "as NEW iPhone"......still didn't fix it. I have an iPhone 6S with iOS 10 GM. I was running the iOS 10 beta before this and have been on the GM since last week......no problems until yesterday.

Has anyone else experienced this? Any suggestions? It was good until just yesterday. Thanks.

 

Yep.......full iTunes restore and set up as new iPhone. Didn't fix the issue.

 

So I seem to have fixed it. I let the phone completely die and then charged it overnight while off, and today it seems to be back to normal? Maybe just needed a recalibration?