Originally Posted by Agosti

This might not be new knowledge but I'd like to share.
I've been monitoring TYO-HKG, and it seems new seats are released 720 hours (30 days) prior to scheduled departure time. You will see availability rolling out throughout the day on AS website, instead of all seats being released at once for the date.
I can't say to what extend this is applicable to other routes. Hope this helps.