This might be cutting it a little close. With a 12:30 flight departure time, you ME pick up time will be around 9:30. I think you need to estimate that breakfast will take 1 hour (sometimes you luck out and the characters will be at your table early, but I think they allow about 40 minutes or more for them to get around the restaurant -- someone will correct me if I'm wrong. Cape May is smaller, so it might go faster). So, assuming you are seated close to your 7:30 ADR time, you'll be done around 8:30 and a cab should get you back to PO by 9:00. However, that's if everything works perfectly. You have a couple of timing screw ups with the ADR, the cab or anything else, and you might be in trouble. That would make me uncomfortable and I would have trouble enjoying the breakfast.