Other added benefits of A2S,
It costs nothing to add flights to your booking 9 months out when flights are first released. They are fully cancellable anytime until final payment and you don't pay until final.
This lets you at least lock in a rate and if you happen to see a better one later you can cancel and rebook or book on your own with one of the carriers that doesn't release theirs until 6 months in advance.
How many times have you watched prices and it never goes down and only up and you are stuck paying a higher rate. This is the best of both worlds unless you are really going to gamble and book flights after final payment.