Premium Class Seat upgrade $15 for MVP Gold 75K - Glitch on the website
During the purchasing steps, Alaskaair.com was charging me $15 each way for upgrading to Premium Class. I confirmed that I was logged in as myself and my mileage number was in the reservation. Called into AS and they confirmed that this is a glitch. Interestingly enough, I choose a regular seat and within minutes of purchase I was automatically upgraded to PC.
They are working on it to be fixed and complimentary upgrades to work as part of the reservation.