The rules are pretty clear with regard to no upgrades for award travel. Even so, award travel upgrades happen occasionally but are really at the discretion of the gate agent.

Just my personal opinion here, but I would never ask about an upgrade when traveling on an award ticket because I think the very act of asking for something when I know full well that Alaska's policy doesn't allow it would strongly suggest a misplaced sense of entitlement on my part. On the other hand, if for whatever reason Alaska's personnel wish to offer me an upgrade of their own volition, who am I to turn them down?

That said, I've been upgraded a number of times while traveling on award tickets. THANKS, Alaska!