Battery

[mark-d]

Mark,
I find that battery life is mostly impacted by the location services and Bluetooth links... I know you mentioned that was not the issue...
Technnically you should have ti restart from scratch : Backup your phone to itunes and do a DFU, not a reset...a DFU is using iTunes, it loads the new OS from the web and not the one stored in the phone (which may be corrupted).
I feel your pain with the Apple store visits... going ot the Apple store is like going to the dentist... new batteries aren't too expensive, you could get it fixed at a third part repair shop, without the genius wait.

The iTunes restore with a new downloaded iOS is what I did

As regards the repair store I don't want to invalidate the warranty