I think there is a much stronger chance of training people who are not currently flying at all in CX onto the A320 before hiring anyone. A lot of those not flying are very keen to get into anything that is moving for job security. The last round of 747 spots were rumoured to be massively oversubscribed.
If any hiring of external applicants one would think it would be to Air Hong Kong (A330) or Hong Kong Express (A320) first. Hong Kong Express was to get half of the A321neo order, rated A320 pilots would be a LCC priority.