1st time trying to use RPU, but I wanted to ask the experts first. Here's the situation:

I'm going to try to help a friend get upgraded on a one-way SFO-JFK flight (non-ps) with an RPU.

She's planning to fly on 2/1/14. I see plenty of R and RN space. When I do a dummy economy booking $179 and I view seats, it says business is all sold out. When I go specifically to buy business class, all the seats are empty and available. I assume some kind of block or restriction?

Anyway, if she books the economy ticket, and then I apply the RPU, it should clear instantly right since there is R space?

Also, when do you think should she book by before the R availability starts running out?

Thanks,

Tom9984