Originally Posted by
SchmutzigMSP
That's not entirely true. Once you change to, say "F" class, you will gain a lot more flexibility as the ticket will become refundable, may have much less strict stay requirements (i.e. no minimum stay, no Sat. night stay, etc), and probably allows subsequent fare changes at no additional cost.
I hadn't thought about the refundable fares, or change in fare rules. I would assume there is some sort of promotional First Class fare which has restricted rules.
When I said "strictly a class-of-service upgrade" I meant, in comparison to a schedule change, which is, in my opinion, acceptable for a change fee.
Regardless, I think that NW might sell more first class tickets if they offered an op-up (based on fare class, route, and distance) since most people don't price first class tickets at all. Of course, then you take away one of the most powerful benefits of the WorldPerks program - the free elite upgrades.