I highly doubt they're going to put out a product under their name that has such an obvious defect after six months. Something tells me they cracked this fully, and that's why this phone has been in development for over a year, so they can get actual long-term repeated use of it to see just how much this "crease" will or will not show.

It's Apple, not a budget Samsung. They 100% would not put out a product that starts having obvious lines down the center of it after using it for a couple months. You'll see when the 6-month reviews come in.