Foxxy, excuse my ignorance on such matters, but as the helicopter in question was operated by a legitimate UK AOC holder, (Alan Mann Helicopters), surely it doesnt matter what the country of registration of the aircraft is.
Regardless of who coughed up the operating costs, it's still a charter - just as the Flightline BA46 was.
There are a number of UK charter operators whose aircraft carry flags of convenience, and they all provide UK crews, airports and the government with an income.
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It wasn't me.