This is also true for all AA metal flights - you`ll land at T2 when arriving on AA (if you manage to snag an award ticket on AA 70).. Plan for at least a 20-minute time window to get to the long-distance train station from when your bags are delivered, and with immigration, customs and baggage delivery wait times (which can be hit-and-miss, I've experienced everything from under 10 to 45 minutes) .I'd not be comfortable with less than 90 minutes of buffer time.between flight arrival and train departure.
The buses can be very crowded , but I still prefer them over the train because that requires tons of escalator rides and even more walking.