My husband and I each, in our own Advantage accounts, have enough miles for first class awards TPA to LAX. AA currently shows award availability for 2 people on the selected flights. However, I'm afraid that if I go ahead and book the flight using the miles from one account, when I go to book the flight from the second account it will show no availability. Any way to make sure this doesn't happen other than calling AA to make reservations?

Thanks in advance for your help.