Can confirm that ANA typically does more releases 3 weeks before, and the availability updates throughout the day.

But to add to that, there are times that they go back and release way more than 1-2 seats. For example, I tracked a pattern of new releases each day from NRT-YVR 21 days out, and clearly remember none of them exceeding 2 seats, but suddenly today, one of them jumped up to 6 seat availability for a 18 day out flight.

Probably the most interesting part for me is that I will check available flights before I go to sleep, and see 2 routes posted, and wake up next morning and those 2 routes are gone, but 2 more new routes are posted with new J seats, and again mid-day more released and booked out. Haven't been able to nail down their release pattern to the hour yet though.