@loucas_11, i don't think requirement naman na SG PR or citizen for SG to AU DL conversion. i'm neither pero nakapagpa-convert naman ako.
i think the more important thing is kung gaano katagal na ung license. approved na ba ung visa nyo and may plan na kayong lumipat soon? kasi questionable nga naman sa license conversion kung iilang months pa lang tapos papa-convert ka na agad or pag kinuha lang ung license after the visa grant. obvious na you're just trying to circumvent the process.
strictly speaking, nsw has a rule that an overseas or even an interstate license must be held by the driver for at least 3 years before converting. though i've heard of someone na ni-reject ung SG DL nya for conversion because of said rule pero na-approve naman nung nitry i-process sa ibang office location.
i'm not familiar with the requirements kung magsisimula from learner's in either SG or AU pero kung not much difference naman sa hours required na practice and cost, why not consider na sa AU na lang mag-aral? either way, i will still recommend getting at least a few hours of practice once you arrive here to get accustomed to the way of driving here.