I'll chime in here with some of my own thoughts on the CBR-CX proposition.

oldchinahand is right (as he so often is) about Canberra's relatively low tourist appeal, especially compared to Cairns and Hobart. For context, CBR has indicated they're looking at uni students from HK and China, which figures into the idealised Dec-Jan-Feb timetable, ie students flying home after uni ends and then flying back after CNY and ahead of the new year. (CBR has also said it's chatting with China Southern among others).

The thing is, that's still outbound CBR traffic for the first part – and likely to be accompanied by Canberras also looking to head to HKG and beyond via CX. There's no inbound traffic in any of this until we get to outbounders returning.

It's always struck me as odd that CBR has almost no international flights: yes, a relatively small population (close to a half-million) but it's also an educated and moneyed professional market, being largely public service plus ancillaries. But obviously there are very good reasons for this, including that so many Canberras probably fly CBR-SYD or CBR-MEL and connect there to the widest possible range of international airlines - Qantas, SQ, CX, the Gulf Three, the US Three, Korean and Vietnam etc etc.

There's been some speculation that CX might serve CBR through a tag leg, eg HKG-SYD-CBR-HKG, similar to what QR and SQ once did. The issue QR found with this was the additional overall cost (inc additional crew) simply didn't make it work. So some sort of subsidy would be needed, and you have to think that once the subsidy ends, how likely is is that the route will have become sufficiently profitable to continue on its own right?

In the case of CX, as well, Cathay AU is quite literally going up against the rest of the CX world in terms of aircraft allocation – this is what they're facing with a return to CNS for example, that the case for CNS has to stack up against and superior to the case for using the same aircraft elsewhere in the CX network, either being another new/resumed route or an additional frequency to a high-performing destination. So CBR would need to be a bloody good business case.