That’s probably going to be at the discretion of your immigration office. As a guess I’d say they may well reject your application and you’d need to start over.
If applying via Sydney then look in to the option of the OX visa. Pre the evisa system they sold those for $600 versus the $300 OA. Possibly they still do.
It’s a five year visa and theoretically an option to extend for another 5 years, although I’ve never heard of a single case of someone doing that.
If you apply for a Non OA visa in Australia then you follow whatever the requirements that the Sydney consulate or Canberra embassy require.
If you are asking about getting a year extension off of a Non OA visa then you would have to provide 12 months of international transfers of at least 65k to do so. Whether you can provide that within the first year of the visa is dependent on how quick you can get a bank account and do the transfers.
Most people use the OA as a visa to use for 2 years stay (with the right timing), but it has the caveat of mandatory insurance. Some who are approaching or over 70 find that insurance requirement tough to get.