OK, thanks everyone. I went ahead and booked the regular “Main Cabin” (fare class N) and then upgraded to Premium seats, aisle for my husband and middle for me. But maybe I should do exit row if that is less likely to have an extra-large seatmate?

We fly Alaska exclusively for domestic travel, but mainly between SEA, SFO, and BOI, so we do not accrue enough mileage to earn status. Starting post-covid we flew in First, often with miles, at least until this year. It seems to have become a whole lot more expensive than it was in 2021 and 2022. Mileage tix in First to New York on our date, for a mid-day flight, use more miles (70K) than our recent flight to Tokyo in Business Class on JL (60K).

How can one recognize fare class “U” when it is released? I did pay to make our flight refundable, so could re-book if that gives us a possible upgrade, but without status it sounds unlikely. And I assume we would lose what I paid for those Premium seats.