If you hold a Working Holiday (subclass 417) or Work and Holiday (subclass 462) visa, the main purpose of your visit must be for an extended holiday. You can do any kind of work over the course of your 12 month stay in Australia, however the conditions of your visa limit you to a maximum period of six months work with any one employer, unless you've been given permission by the Department of Immigration and Border Protection to work longer.
I'm wondering the likely-hood of myself and/or her getting jobs in aviation is down there: Unlikely. There are many Australian pilots ahead of you in the job queue.
...what work and costs would be associated with converting the licences?
https://www.casa.gov.au/standard-pag...%3Apc=PC_90024
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