Not an expert on oils by any means but I think in the real world this will have zero impact on your engine.
The difference between 0 and 5 relates to viscosity when cold, 0 as I understand will flow in temperatures as low as -40c whereas 30 will flow in temps as low as -35c, neither of which are likely events in Australia.
What's more relevant is the 30 which relates to the viscosity at 100c, the temperature around which your oil operates when fully warmed up. As both are 30 grade at this temperature they have the same viscosity.
Possibly VAG have made this change so that this oil is suitable for use in all countries?
Cheers
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