Do I as a New Zealander living in Australia have to be in NZ or apply from here in Australia?

My partner and I are applying for a Chinese visa, I am a New Zealander living in Australia for the past year and they are a born Australian citizen. We have flights booked but no other itinerary as we are intending to backpack and travel around a little and wanting to leave our trip as flexible as possible. Do I as a New Zealander living in Australia have to be in NZ at the time of application or can I apply from here in Australia? Also, do you think it would be possible for us to have a multi entry one granted for upto 6 months as we want to leave our plans as open as possible? Our flights are booked for March so does its validity begin the day when it is granted or can we specify a 'start date'. Just want to know the best time for us to apply. Sorry for all the questions! Thanks :)