Be careful with this. AA will tell you that a flight is delayed and then also tell you to be at the gate at the normal time. And ime, the reason being is that sometimes this delay doesn't actually happen, and the flight does board on time when the incoming flight is on time. But AA is able to shake off a couple of barnacles who aren't at the gate if they're overbooked. Seen it happen too many times to think it's just coincidence.