What else could it possibly be? The country can't keep the borders closed forever, which means opening up again, and pursuing Covid-zero until vaccination happened is obviously going to save lives. I think we would have delayed a bit further if possible, to get more people boosted, but Omicron has forced this timing.

I can think of various alternatives but I'm not interested in getting into that discussion. I'm interested in when the earliest point in time was that the NZ government communicated (either internal communication or external communication) that its plan was to prepare as best as possible and then open up.