This is a variation of a past thread:

http://www.flyertalk.com/forum/showthread.php?t=873182

but my question was somewhat different so I thought I'd start a new thread. (GB, please merge if you think that would be better.)

The situation is that I had an upgrade award to MNL-HKG-ICN already issued for my dad and me, but because of a change in plans, we're going to SIN instead. I've had the award reissued to SIN, but only I have a confirmed booking (because of the Gold guarantee) whereas he (Green) is on the waitlist for the economy bookings. I've contacted MPC, and today I received a confirmation email that they have placed him on the priority waitlist.

My question to you: what are the chances that he will clear his waitlist? (I think it's the MNL-HKG legs that are full, but he wouldn't need to use his economy booking anyway because there's an upgrade award waiting to be ticketed if his revenue booking clears.)

In my position, until when would you wait (we planned on leaving MNL on the 26th; the upgrade award needs to be ticketed by the 23rd) before calling it quits, and just doing a mixed class booking (business for MNL-HKG-MNL, economy HKG-SIN-HKG) so that at least I don't lose the miles used for his upgrade?

TIA.