In the past discussions of the release of X inventory for domestic upgrades, the trend has always been that AA will release X seats at tier windows UP to the point that there are about 20% of the First Class seats yet open. For an MD80 for example, typically when at 100 hours (as EXP) we see 4 seats unassigned .. that implies that the balance are Gate Assigned and will be 'field upgrades' rather than tier clearing earlier.

I am on a flight LAX-DFW (a 737) that is X0 and about 48 hours out... There are 6 assigned seats in First and 10 unassigned seats... This goes way beyond the 20% 'rule'. Coach has a good number of seats .. EF is showing F5Y7.. tho showing A3.

The flight after this one (MD80) has 5 unassigned First Class seats and is X1 .. going down to the traditional 20% rule...

Anyone got a clue why this one flight is so far above the 20% rule 2 days out??

I know I know the answer will be Yield Management and the various ways they look at things and decide when to release inventory and all the complexities (mumbo jumbo) involved therein. But the 20% 'rule' has been pretty consistant in my experiences .. and now it is skewed.