LON-SYD can be done by SQ (LON-SIN-SYD), or OS (LON-VIE-SYD). I'm ommitting TG 'cos their J product isn't that great.

SYD-MEL can be purchased internally. No *A flights though I think UA has some sort of 5th freedom traffic rights in between for their 1 daily flight.

HKG-CAN can be done by road or rail.
Internal China flights to be bought seperately.