We're in the process of having our 457 Visa submitted (via allocated migration officer in Aus). His advise states that we need evidence of private health insurance to process the visa but we don't actually need it in place (and want to pay for it) until we are due to arrive around August time. We also need an Australian address to purchase the insurance which we don't yet have. When and how are we supposed to put our health insurance in place for August without holding up our visa application? Any advise would be much appreciated.