Most licensing authorities require at least 1500 hours TT before they'll issue you with an ATPL. Unless you're a high time PPL, I'd doubt you'll have the hours for an ATPL in 9 months. It took me about 3 years flying in GA to get those hours.
If you wish to fly in Australia for the most part of your career, I'd forget about getting an EASA CPL. Start studying for the CASA CPL ground subjects now so by the time you're here in September, you'd have your ground subjects done and you'll be ready for flight training.