That was exactly my problem with bleeding. Hexxed explained it perfectly too, very faint but it seems like a pressure point at the edge. I hated it and I'm OCD so I want perfection, I eventually got it replaced today. I called Apple and I wont going to budge on waiting I wanted it now, so they hunt one for me. Granted it was 45mins drive... I'd rather drive that than wait 2-4 weeks or so.
Advice to everyone who have issues, contact Apple and demand same day replacement. Do not settle for less. I told the lady I am not waiting for a Genius Bar appointment, which would be at the mercy of Apple stock. Or order a new one with 3-4 weeks shipment. The Plus is super high demand so ymmv. Good luck