But isn't Y-fares the ones that are automatically upgraded upon checkout whereas the B,M,H,Q fares you have to wait the normal clearing time?
Also if A fares are first, what is the equivalent for business class fares? It doesn't seem like D-fares are "Y-UP" fares. Does that mean there is no upgrade availability?
JFK-LAS feb18 830pm
LAS-JFK feb21 11pm