From 2.3 you'll need to head to the dealer - the step up on 2.3 to 3.0 may also require some hardware changes/updates (a heavy duty 12v battery and possibly a controller or two, I've heard). 3.2 update might be done at the same time, and that looks at replacing modules in the main battery.
You can paste your VIN at VWs Australian support site to see check if any service campaign and/or recall applies to your Volkswagen vehicle: https://www.volkswagen.com.au/app/locals/owners-service/service-campaigns-recalls