Qantas has again dropped their prices for flights to Beijing. They've knocked off another $28 off the Auckland fare, $66 off the Wellington fare and $28 off Christchurch. They've also added loads more dates including June, October/November and March 2018. These fares include bags + food. All of these connect via Sydney.
Use Qantas' website and search for flexible fares to see where the cheap dates are.
Auckland-Beijing $627 - Skyscanner via BYOJet - Momondo or book direct for $649.
Wellington-Beijing $623 Momondo or $645 if booked directly.
Christchurch-Beijing $616 Momondo or $637 if booked directly.
This is part of the Qantas Global Sale so check out the other destinations also on sale.