I've been researching availability for this Friday IAH-LIT since I need to take an earlier flight. I'll likely SDC (Premier Gold and no fees can't come quick enough), but I came across some interesting pricing on changes.

The system is quoting $422 fare difference + $150 change fee to change to an earlier flight Friday. That's $572, and it books into H class. If I book a NEW, one way ticket by itself for Friday, on the same flight the change is quoted for, it is only $225, and books into H class as well! (currently in L outbound and W inbound).

I think the reason is that my return flight (Sunday night), only has availability in B, since a new round trip with that itinerary would explain the $422 fare difference. However, since my return flight is confirmed in a lower fare class already (W), and I'm not seeking to change it, I wouldn't think this would affect anything. It seems silly that booking a new 1-way ticket would cost half the price of the change.

Maybe someone can explain this difference. Also, I'm curious if I did book the new one-way (though I don't plan to), would I be allowed to merge the itineraries, or would it invalidate my original ticket when I didn't take the outbound flight?