Well every country will have to go through this phase. If you are 80% vaccinated would you still expect the country to close up forever? If you are unlucky and infected your body has more immunity and antibodies than a jab. So with both the jab and the infection, the covid in that country will eventually be like a flu.
Also, all covid virus have the same incubation period. In fact, a shorter time for delta. 21 days or 14 days quarantine is nonsense. The same covid strain from the UK incubates just the same amount of time as the strain from NZ.