The only alternative interpretation (possibly even more stupid) is that overseas-registered aircraft are subject to a more onerous equipment regime in UK airspace than are UK-registered aircraft.
Having read it again I'm starting to think that maybe this the answer...surely though this has been answered before? Although I couldn't find anything on the search. (Why can't they scrap the four word seach minimum?...Its such a pain in such a acronym dominated activity.
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