Lucky you - for us and many companies these days the rule is only economy class for all employees, regardless of distance/time.

I think that the criterion for any invitation membership is likely to be not so much the travel of the individual but the travel spending which he is able to direct towards CX. I know this is the way the BA scheme works in HK. Hwoever, since CX is in any case the default or only airline for many routes out of HK the expenditure you could direct to CX would have to be pretty huge before they would consider the invitation.