Knightstar - I posted your note on the OCC Facebook page and these are responses posted there.
Spruce Ohlson We are currently in Tongatapu and heading south to NZ in a couple of days. Only advice would be to hurry up as cyclone season is drawing close. You can clear in to Tonga in Neiafu (Vava 'u), Pangai (Ha 'Apai) or Nukualofa (Tongatapu).
6 hours ago · Like
David Bridges Did this same trip in 2001 via Nukualofa & North Minerva Reef.....and sailed between NZ & the tropics for a total of 5 trips......best advice I have is on the leg south to NZ carry all of the fuel you can & keep up your speed in light weather, don 't mess around because heavy frontal weather comes regularly so the less time you are out there then the less likelihood you are to get caught in the headwinds. Enjoy!
Vice Commodore, OCC