It's already started:
https://thedriven.io/2019/03/08/plu...nd-is-nigh-for-fossil-fuel-cars-in-australia/
https://www.caradvice.com.au/789598/vfacts-august-2019-new-car-sales-detailed/
About the only category of vehicles with rising sales in August was petrol-electric hybrids (up 55%).