Definitely not guaranteed. However, I would say your chances are good since the window between BA vs AA is only 30 days (~360 vs ~330 days) considering you're going to book them as soon as it opens on AA. There's probably a good chance that it will go back into circulation that far out.

I'm guessing you want to book in J and not F (F is a little bit more tricky since the inventory is so limited -- usually just 1-2 seats per flight or none at all).

Now it's a matter of risk vs benefit analysis. Are you willing to risk losing your award ticket on BA and $55 just to save some AA miles pre-deval?