Guessing the rules of a complex algorithm is never easy..

I had a discussion with a well-informed guy at HQ and he mentioned that CX went through several iterations over the years.

Many factors are taken into account, maybe the result is what you refer to as CIV. My discussion focused on opup from J to F on longhaul. Of course, that is rare because there are only 6 seats and some pax upgrade with miles or opup certificates.. But it seems that they take into account many factors like your flight history with CX (even if you are not a MPC), fare bucket and, of course status.

Just an anecdote: I was flying in paid F to Europe and my wife in paid J (cheap fare bucket, OWE with BA like me). She got opup to F at the gate. I knew for a fact that they were DM in J (friends/colleagues) who were paying higher fares. This was done by the algorithm and she did not ask for opup.

It is interesting to see that different aiirlines have different philosophies for opup. For example, AF does reward loyalty a bit but seems to use opup as a marketing tool to "attract" infrequent AF pax, such as people with other ST FFPs who infrequently fly AF. I am talking here about opup from Y/PE to J. And if you have been opuped previously, your chances of a new opup are reduced.