People here have short memories.
AirNZ used to operate NZ240/NZ241 as a CHC-RAR flight during 2009 to 2011 with an A320, I believe it was also seasonal.
As it only operated for a few years, it may give an indication of how viable the service was vs directing everyone through Auckland with its larger Pacific Population.
Air Pacific/Fiji Airways have been long term flying CHC-NAN, however it has fluctuated between once a week, to twice a week, to seasonal.
South Islanders and trips to the Pacific tend to vary a lot as it is always going to be easier (and cheaper) to get to the Gold Coast than going to the Islands.