Ok, the reason I'm told is that the international convention this year in Melbourne did not invite all states to the Melbourne Marvel Stadium.
In 2014 some 70,000 Australia wide witnesses attended. This year they aren't allowed to use the playing field for seating so the capacity will only be about 50,000. They anticipate app 6.000 international delegates.
Those states not invited are having regional conventions with the same program at various assembly halls.
In QLD its at park ridge.