Chris, I grew up in the western suburbs of Sydney (Seven Hills) and there are fireflies there. (Well, there was when I left in 1975). I also used to see them every year on holidays at Port Macquarie, Lake Macquarie, and Wangi.
I have seen them in their thousands at Jenolan Caves, and when I lived back up in NSW for 1 1/2 years only 5 years ago they were at Budgewoi and Toukley.
There is also a place about 10k from where I live here in western Victoria called 'The Devils Kitchen' and they are there too.
I took it for granted that they were everywhere