After getting the visa, both countries will automatically reserve one year for you, which means that if you get the visa on 20 17.04. 16, you can enter the country on any day on 20 18.04. 16.
So if you want to apply for visas for two countries, go to Australia immediately, and then wait for almost one year, that is, when the time left by New Zealand is about to expire, and fly directly, the air ticket fee will be much cheaper.