I'm not CX staff, but had my last staff ticket to HKG issued as a Cathay one (I work for a UK regional with BA affiliations). Sorry to say I'd never do so again (based on my own experience and that of my elder brother, a CX F/O).
From the get go the LHR staff were rude, obstructive and made it clear I wasn't welcome. The treatment of their own staff waiting for a flight was hardly better.
Fast forward a couple of hours and trip to T5 and my experience was night and day. BA sorted a ticket with minimum hassle and the CSD was kind enough to come down and apologise for not being able to find me a better seat on the full flight (I was glad just to get on). I was spoiled rotten for the rest of the flight, same on the way back.
From the outside looking in, I'm afraid this seems to be Cathay's MO. At one time I'd have given my left nut to join. Nowadays it seems there are much better deals, even as pax.