Auckland is two hours ahead of Melbourne, consistently. New Zealand and Australia both observe daylight saving and the offset holds at two hours through most of the year, widening to three for about a week each spring when New Zealand changes first. Practically, that means a New Zealand morning incident is raised into an Australian team that is already rostered on, and a New Zealand overnight change window sits in the small hours of both countries.
The harder question for a New Zealand organisation is not the clock. It is the one about jurisdiction: a New Zealand agency or regulated business has to be able to say where its data sits, who can reach it, and under whose law that arrangement operates. Those are fair questions and they deserve a direct answer rather than a reassurance.

