Thanks for the tips. I have gotten a few from Coupon Connection lately that expire 2/29 and noticed they say they are valid on "Y or YAS" fares for confirmed space upgrade, and at airport on day of flight on other fares.

1. What is a YAS fare? (Y fares are pretty pricey -- e.g., RT discount SJC-SEA I can got for about $170, RT Y is $560)

2. When they say "at airport" is it first come first serve for NW platinum elites on AS, or are you ahead of non-elites with coupons in priority to get the upgrade?