If you leave Australia after your travel validity expires, or it expires when you are outside Australia, you will not be able to return to Australia as a permanent resident. This visa allows you to return as a permanent resident.
Basic Eligibility
an Australian permanent resident
a former Australian permanent resident whose last permanent visa was not cancelled
a former Australian citizen who lost or renounced Australian citizenship. Australian citizens are not eligible to apply for an RRV.
With this visa you can
travel in and out of Australia as many times as you want until the travel validity expires
have a travel facility up to 5 years depending on your circumstances. See About this visa.