The Australian Energy Market Operator (Australia’s independent energy markets and power systems operator) and the Australian Energy Market Commission (which sets the rules that govern the electricity and natural gas markets) both offer information on the Power of Choice review and its resulting rule changes on their websites:
AEMO: https://www.aemo.com.au/Electricity/National-Electricity-Market-NEM/Power-of-Choice
Each state government also has information available on Power of Choice:
NSW: https://energysaver.nsw.gov.au/households/understand-your-usage/smart-meters
SA: https://www.sa.gov.au/topics/energy-and-environment/meters-and-bills/smart-meters
VIC: http://victorianenergysaver.vic.gov.au/bills-pricing-and-meters/smart-meters-and-how-they-work