Ok so have some news to share.. after getting a little tired of the lack of information I sent another email to the Melbourne delivery team. I got this email reply this afternoon that revealed just how big the delivery challenge is.
Tesla typically don't talk about sales numbers outside earnings calls, but looks like the Model 3 has sold amazingly well in Australia - https://techau.com.au/tesla-has-sold-thousands-of-model-3s-in-australia-making-it-the-best-selling-ev-in-the-country/
The data backs this up plus multiple sources indicating the same. Another good article.