I think what you want to know is if there is a Z seat available. I think?

Here's your flight:
F9 A9 Z0 P0 J9 C9 D9 I0 U0 Y9 B9 H9 K9 M9 R9 L9 V9 S9 N9 Q9 O9 G0 T0 X0 E0

So if my reading of the codes is right you're booked in U now, have the "right" to get Z if it's available, and want to know what to do?

I think the answer to this question is get a subscription to Expertflyer, which is very cheap. Then enter a flight alert that looks like this:

Create Flight Alert
Departing Airport JFX
Arriving Airport SYD
Departure Date (mm/dd/yy) 11/9/06
Airline QF
Flight Number 8
Class Z

And then wait around to see if you get an email when they make Z available and then call and ask for it. Or alternately just check back, etc.

I use EF a lot but never for QF so someone correct me if I have the codes wrong or something. And subscribe to EF. It's worth it.