Hi - I'm flying a redeye tonight, AA1806 SEA - ORD. I am checking in online and getting the message "We apologize we are unable to pre-assign seats for your reservation. Please check back on AA.com or obtain your seat assignment(s) at the airport on day of departure. "

When I booked this ticket there were also no seats available. Does this mean the flight is fully booked? I thought most red eyes flew substantially below capacity.

I've checked a few times since I booked the ticket and have never been able to find a seat.

If it matters, I paid for about half this flight with a voucher.

edit: forgot to mention that it is the same on my return flight, AA1377 on 05/15/2011. I'm connecting through ORD to a small airport in IL and I am able to change my seats on the small puddle jumper flights.