Hi gdiphil -
I looked at the travelmood website to get the current offers. They quoted £1200 to fly economy to Dubai and then business to Sydney. I was due to come back business to Dubai then the last leg in economy.
The best thing was that I was in Sydney long enough for the miles from my outward flight to be posted to my account so I had enough to upgrade the final stage of my return flight.
It's worth keeping an eye on these offers. At the moment, for example, they have a combination of business to Dubai and then First Dubai/Sydney for £1800. Bargain !
They also have a THAI combination of economy outbound and business return.
Good luck.