In a rather weird, and almost certainly unrelated coincidence, NZ901 early in the flight made a position report to Auckland Oceanic HF that they were over Queenstown then just a minute or two later corrected that to Invercargill.
Although I clearly remember this being discussed in the Ministry of Transport, Civil Aviation Division, Head Office I have never seen reference to this in anything related to the investigation or elsewhere. As I say, almost certainly unrelated though it does cause one to wonder.