I have an MIA-DOH-CPT booking in Sept booked through AA. I'd really like to cancel and book with Avios instead since I value AA miles a lot. However, I can't seem to figure out if availability returns to inventory right away. Would the safest way to do this be to call Qatar, and once I have them on the phone, then cancel the AA booking and start the whole thing over? I realize the fees are higher on Qatar, but 150K AA miles are at stake.