I'm trying to book a flight from Colorado Springs to McAllen, TX.
If I perform a 'standard' search (from the front page), it shows me Economy ($279), Economy-Fully Refundable ($329), and First ($529).
Now when I go to 'Advanced Search' and try to use Plus Points to upgrade, it only gives me the option of booking the basic Economy ($279). I'd rather do the $329 as I figure that'll give me a better chance at upgrade, but it's not an option. I even went in and selected W, E, B, and M fares, but same thing.
So that's odd...and something I can't figure out. Is there a way to force the site to allow me to purchase the $329 and use PP? If not, which is going to give me the better odds of upgrading--the fully-refundable $329 fare or using the $279 fare with PP? (Btw, both fares are W class...so I assume that's why it's showing up like that.)

Do not use the upgrade option on Advance search, it is not unusual to have issues.

Purchase the fare you want without PlusPoints and than apply the pluspoint request after purchase.


W is W, refundable or not does not change the upgrade waitlist priority

Sometimes it can work in your favor. I've found lower priced fares doing the upgrade advanced search then just selecting "buy economy"