Originally Posted by
craigthemif
As others have jumped in to say, you can't combine an Avios booking with a cash booking, especially on another airline.
And that's exactly what my post is saying. I was talking about avios+avios, not avios+cash.
A one-way HKG-MEL in Y using avios is 25,000 avios plus 40 odd quid - I'd be surprised if OP could find a better value one-way cash flight than that on CX, even leaving aside the connection question.