The person checking the boarding passes at the beginning of the queue sends premium class passengers to the TSA boarding pass/id scanner next to PreCheck (which is on the extreme right when facing TSA). This is the same queue that non PreCheck passengers from AA’s flagship checkin end up in. While typically shorter, this queue isn’t necessarily faster since all (?) passengers with assistance end up here as well- sometimes cutting in from the regular queue (I have on occasion backed out from this queue to the ‘regular’ queue on the left when facing the TSA because that was moving faster).

Post this scan, you could go to/are guided to any of the regular screening lanes. IIRC the leftmost one has the newer scanners, and at times, I’ve been told to leave electronics inside the bag.