|State||Spring Holiday||Summer Holiday|
|NSW||26 Sep - 7 Oct||19 Dec - 26 Jan||Link|
|VIC||26 Sep - 7 Oct||23 Dec - 31 Jan||Link|
|QLD||19 Sep - 30 Sep||12 Dec - 20 Jan||Link|
|WA||3 Oct - 14 Oct||19 Dec - 31 Jan||Link|
|NT||3 Oct - 7 Oct||19 Dec - 27 Jan||Link|
|SA||3 Oct - 7 Oct||19 Dec - 27 Jan||Link|
|ACT||3 Oct - 14 Oct||22 Dec - 2 Feb||Link|
|TAS||5 Sep - 16 Sep||22 Dec - 14 Feb||Link|
So, if you're planning any activities with schools, then the blackout period this month is effectively from 16 September to 14 October, and then for the summer holidays, you’ll need to get any activities completed before Friday 16 December.
The list is in completely random order, mainly because of my poor searching skills!