Adelaide should move to the eastern time zone and here's the reason why. Lots of us now have solar panels on our roofs, now as the sun will set 30 minutes later than it does now, we will all benefit from an extra 30 minutes of sunlight.
If this extra sunlight occurs in the middle of the day, which it could because I want it to, then personally I would generate an extra 1.8kWh.. PER DAY..!
This benefit would outweigh any negatives such as your curtains fading sooner. It seems like a win-win to me.