IOS 10 bug or something else? (Stuck in recovery)

Hi everyone,

Last night I noticed something really strange with my iPhone 6S Plus.

For the past few generations of iPhone, if I ever wanted to get the battery reading to be accurate I would turn off the phone and then connect it to the charger. It would then just switch on. Gives it a fresh start.

What happened last night, was that the phone was plugged in but just stuck on a black screen. It wouldn't power on and it appeared to be dead.

I plugged the device into the PC and it kicked into restore mode, which was odd in itself.

The phone for whatever reason, puts itself into recovery when the charger is attached with the phone off.

I did put the serial no. into the 6S battery checker and nothing was flagged.

Has any one seen this before and know how to prevent it?

Thanks

 

Went to Apples local authorised repairer and they advised to send it off. Got home and tried again, managed to get the restore done. Makes no sense at all.

Why would plugging a phone on charge with it powered off put it into recovery?