I totally get how closing the park down for a month or two in the offseason would allow the park the convenience of being able to carry out preventative maintenance and upkeep on non-attractions such as shops and food outlets.
But how exactly would it make it easier for them to do maintenance on attractions? If the ride is closed - it's closed. Allowing them to space out their ride maintenance across the 8-non-peak months of the year means they need less maintenance staff at once.
If they had to do annual maintenance on every attraction in only the space of 2 months - it would require a far larger (temporary) workforce - and with it would come the problems of retaining those staff until next year, or having to retrain all of them each time, plus the higher wage costs associated with hiring contract, casual or non-permanent labour.
Parks overseas can do it because literally nobody would visit the park in the offseason... you know - snow and all... But Dreamworld is established as a 364-day a year park.
If they're going to change operations like this - they're going to need to buy an 8 foot tall talking moose, and take out insurance against armed holdup.