Originally Posted by
Austinrunner
No "rule" can be gleaned from those observations. Anytime or never is the answer for any flight.
I've no doubt that you're correct that AA can release seats anytime (within 331 days) or never. However, on the route that I'm watching I'm seeing exactly the same pattern that kentleytx describes. Each day Milesaaver seats are released for an additional day, always 320 days ahead.
I'm not saying that this is a general rule that can be applied to all routes or at all times but at the moment it seems to give a good guide as to when Milesaaver seats are likely to be available on several routes.