Originally Posted by fumje

If you're already at the top of the list, no point adding PlusPoints.

I agree with HNLbasedFlyer that there's a good chance at least one of the last two seats gets bought.

As others suggested, changing flights may be a good option if your schedule allows. Pretty much any of the other SFO-HNL flights tomorrow looks better for your upgrade chance. Try checking in online or with the app and see if it will let you change. I think you can clear CPU on any of them except the one you're on.