It is unlikely that there are suddenly, this year, five times as many golds and plats as before.

It's likely that either:

1) Corporate travel departments are suddenly snarfing up F fares or Y-up fares at never-before-seen levels;

and/or

2) NWA is experimenting with offers to corporate agencies and/or travel departments or making F available at discounted rates to individuals, so that F is filling up with people who are "paying" for F well before EUA runs, at never-before-seen levels.