Re: matches going forward...
NZF will be looking to secure European friendlies for March once Euro 2020 qualifying ends this coming week and it's known who's free (16 teams will be headed to playoffs).
The Nations Cup is going to be held in June 2020, as per the Fifa letter posted. There is talk this could effectively be used as buildup for the OlyWhites heading into Tokyo.
OFC World Cup qualifying is set to start in September 2020 and take up the three windows at the end of 2020 and two of the five in 2021, leaving one or two windows at the end of 2021 for the remaining Oceania team to prepare for the March 2022 intercontinental playoff.
There should also be a free window or two early in 2021 for potential friendlies.