Originally Posted by
AussieInLondon
you can still return, they will never close the country to citizens. Leaving is also not too difficult as a non resident, though I recommend applying for your leave exemption at least 3 weeks before you need / plan to leave.
My understanding from the website highlighted earlier is that non-residents have no issues leaving and need no permission. Apparently border control can check your movements quite quickly to prove you haven't lived in Oz for a length of time. Also, I travel with both Aust and UK passports.