While so many of us worrying about the connecting traffic on the London side, I think the O/D traffic between Hong Kong and London is pretty strong, and also CX got the transit passengers from whole Asia and Australia/NZ, I can't see how this route can be failed.

Also, with the A350 coming and low fuel price, tough the LGW flight will not be as profitable as other LHR flights, I would expect it can survive at least with a daily A350.