CX fell foul of UK revenue because they use the term 'base'. When the system was first set up to accommodate VETA, the company used KPMG to do the research and had a letter to say that what they were doing was acceptable and that responsibility for paying tax was down to each individual crew member. Many lived outside of the UK so the question of tax did not arise.
The revenue people had another look after the Crofts case and decided that CX was now an onshore company. If you are going to change the rules retrospectively, make sure you work for the government. CX protestations were met with "That was then. This is now." UK is now clearly 3rd world in its attitude to the rules. Like many areas of taxation, there is no law; only precedent. A judgement in court is required to make the precedent law. Hence CX fell into a grey hole.
Other companies allow their crews to have time off in Europe but do not nominate a base. On arrival in Europe the crew member is given a ticket to wherever he wants to go, (within reason, of course). I am surprised that CX did not follow this path; unless they did not want to rattle any cages. Opening bases in continental Europe will be interesting. I have just read that social costs for an employer in France are 48% of salary. Anyone know what the costs in other countries would be? I suspect that London will be the only European base, since social costs are only 12.5%.
Way forward is to make everyone HK based with a European biased roster, as do other companies. Save a fortune.