Short answer: If important to sit up front, spend the $$. Success will vary greatly, based on route, season, schedule, so it is very difficult to predict with any level of certainty.

Longer answer: Through the first half of 2023, this would work well SAN-KOA / OGG. It seems that AS has done a better job selling F / more leisure passengers are willing to buy F. to the point where there is no need to leak advance U inventory. 50/50 as 75k with T-24 upgrades due to no-shows, cancellations. Schedule flexibility allows us to travel midweek, off season, so it does not appear to be an issue of timing. Becoming a bit concerned now that KOA-SAN has become a redeye, I am dreading an overnight flight in Y+.