Not sure if it's been covered before, but I couldn't find anything on this thread. I've been following the flight status of AC812 YUL-LIS just out of curiosity because I'm flying it in a couple of weeks. I notice on the upgrade list where it shows how many seats are sold/checked-in... It's never showing of 32 seats. It's always something like 16/31 or 15/30.. I thought it might be due to broken seats, but when I look on expert flyer, I don't see any blocked seats and wonder why when there are 8 rows of 4, why it isn't showing X/32?