Looking for this information I came upon the old thread.
What I also found looking at BA award seats using the AA.com is that they load the seats sometime after midnight for 331 days out but if a connecting flight is 332 days out...even though they show the award ....when you click on it a notice comes up saying that award is " no longer available".... just their way of saying you are a day too early to book the whole itinerary.