Who are you flying with on the Auckland - Shanghai leg? Partner redemptions are notoriously difficult, as you can see from the sticky at the top of the forum.

You can do dummy bookings on the website to check availability or you can ring the Flying Club - availability of G's (Upper reward seats) can appear at any time prior to the flight - I think the Shanghai flights are usually very good for reward seats, but the Flying Club will tell you for sure.

Nick