What do you mean? Are you saying that the extended warranty will not be available in Australia?
Not sure if it will or won't be available. Just haven't seen it mentioned anywhere. Maybe it becomes available when you register as it's not showing as available on the MS store. Not sure.
Apparently when you register the SP3 and nominate Australia as the location it extends the warranty to two years under Australia consumer law. But that's just manufactures warranty not accidental damage cover.
So I don't know either way for sure.
Wonder what happens if you register the SP3 and then return it does that effect anything. Unlike the US we only get 14 Days to return but that should be enough to try it out.