Honestly this sounds like nonsense. The law should apply equally - you have a UK company formed earlier, UK will no longer be part of EU -> same law applies to you as as to a newly formed company.I just thought, that the companies were started before the Brexit happened. For a Holding company, the companies have to be within EU and at the incorporation, they were part of EU member states, so the EU law about holding companies still apply, because they were incorporated before the Brexit happened. I dont know for sure 100%.