Tried booking a trip with U space so I could use a GGU. When I filtered for Gold upgradable flights I got N on the outbound and Q on the return. Bought the ticket, upgraded the outbound fine, but the return won’t upgrade because it’s Q.
Not sure why Alaska even shows Q in the GGU results. Bug maybe? When I try the same search again I get N on the return if I pick a premium class fare.