I recon it's not gunna be a cold weather problem for you lol.... so maybe something to do with intense fertilizer at the wrong time, or loss of roots to chewing grubs. Thats what I'm going to guess after reading that last link above.... as there were no photo's like that on the QLD site to identify it as as disease at all
So that only leaves something on site that's different to usual. So that's where I'd start my thinking on it all.