Australia has already switched off 2G services with the largest telco (Telstra - formally government owned) having announced the future switch-off date for their 3G services, they have given about 5 years notice and no longer sell any phone that don't support 4G. They followed a similar process for the 2G switch-off. Vodafone and Optus then followed Telstra's lead to switch-off 2G. I wouldn't be surprised if they also followed in a similar timeframe for the 3G switch-off.