I am booking an award trip in Y from DAY-LAX for next week. When I go to select seats, I get the message "no seats currently available for advanced seat selection." I understand that seats would be assigned at check-in. At 24 hrs. before departure I know that I can check-in online, will I be able to select seats at this time, will available seats have opened up, or do I have to get seat assignments at the airport only? According to the current seat chart for my flights, only "Preferred" seats show up as available. At check-in, if these are the only seats still available, would I be able to select one of the Preferred seats, and can I select online 24 hrs in advance or at the airport? Thanks!