I've never seen this "Refundable Premium Upgrade" before. The search I did was https://www.alaskaair.com/search/res...ty&UPG=goldupg (Gold upgrade). The fare rules say "Fare Application: ECONOMY SELL-UP OW REF FARES N APPLIES FOR ONE WAY FARES FOR ADULT". I'm not quite advanced enough to find the matching fare in Matrix or EF. What's going on here? Why isn't it just a normal N fare?