I don't think there was a base option but the application did ask if you would be prepared to move at the companies discrection, standard application stuff.
The aircraft will be on the ground for long enough in Sydney to do a Perth or Auckland return so likely to be utilised on this route. I think its highely unlikely they will open a Perth crew base anytime soon. Doing so would just introduce extra costs into the equation. Sydney crew would be used for the return trips.
Fingers x'ed for you.