Dude why would you wait for a genius appointment when you are under your return day limit.
I bought a 6 plus that had a screen defect, that night i reserved another one of the same model and just took the defective one in and demanded they exchange it for the new one. they did it right away. You shouldnt have to wait for a genius bar appointment if you can easily just refund the phone and get another one.
The girl just asked me what was wrong with it and why i was returning and i showed her the phone and she just replaced my phone on the spot. no genius bar appointment required