On a similar topic, I'm scheduled for a flight on a 777-200 on 14 April, CDG-BOS, AF338.
This is showing J to be rows 1-5, including 5A and 5B. The seatguru seat map doesn't show 5A and 5B to be valid seats.
http://www.seatguru.com/airlines/Air..._777-200_B.php
Is this a new cabin layout?