Bolty,
Before the A345 all Oz flights (with the exception of Perth) were via SIN. These flights still remain (although SYD is now via BKK), and the direct flights have been added as additional ones. I think with the extra flight to Perth about to start all the allocated EK slots into Oz will be used.
Not sure how to answer your question, but the flights DXB to Sin are always full. Flights SIN to Oz vary from always full, to mostly full. Read into that what you like.
Don