Fwiw another tactic below:

Since you want to guarantee it, let's say award inventory isn't available but you can tell via EF the flight seems wide open. What I recommend doing is don't book the cash ticket via the website, since (barring the 24 your hold) you must ticket immediately. If you call reservations they don't force you to ticket it for a while. Then, put yourself in the waiting list. (Theoretically) Asia Miles / MPC members have this mechanism, which is "swept" first before award availability goes to partners. In practice it sometimes fails to do its job, aka somehow partners end up with availability and you're STILL on the waitlist (!!!), but I've had enough successes to know it at least works "often" if not always.

Anyway, this could be a backup plan of what you want isn't immediately available, and prevent you from spending the cash unless the upgrade comes through. IF you clear the waiting list, then you can ticket your cash PEY fare.

As to your other questions, you can use the Asia Miles website to search manually. It's not that bad.

Unfortunately for you, dropping from GO means you lost one of the best "benefits" of CX elite access.....the ability to reach a call center agent in less than an hour .