I would suggest that you call Apple support and discuss the issue. Probably
Better to speak to someone who is accountable at the end of the phone line and can action on your behalf.
They should run a diagnostic test over the phone With with you to verify battery drain and life cycles of the battery etc.
They wil be able to check your serial number as they did with me to determine if it is one of the known affected phones.
Further to that irrespective of the outcome on the call in relation to your serial number, you should book an apontment with the Genius Bar. The Genius Bar will run the same diagnostic tests and discuss how the issue has been affecting the phone.
There will be a standard protocol for the representative to follow should your phone be outside the known affected serial range (which mine was) after the press release and at the point of bringing it to Apple for the second time.
You will have to have conducted the following tests:
- Reset phone to factory settings 'Settings>General>Erase all content'
(I would suggest before doing so to backup your phone to the cloud and also created an encrypted backup via iTunes).
The phone should not be restored from the backup to fault diagnose that this is a SW/HW issue related to the phone and not a symptom of a broken install.
- Erase and restore to backup so that you have all of your apps installed and signed in as per full previous operation. The encrypted backup will restore all password settings inside apps which the iCloud backup cannot.
It is good to have an encrypted backup made especially should you be getting a new phone when you visit the Apple Store.