That website accurately describes the scenario for which the equipment was used in this instance. It can't exactly be top secret, someone must have seen it take off from somewhere. Perhaps the equipment lowers down a trap door after takeoff so the atc at Canberra don't take photos of it and put it on YouTube like they have before :-)
Yes that one was at Avalon this year. It's not impossible for it to have been flown over for the job.