Nonetheless in the UK Beagle's statement is correct.
Insurance companies and airfield operators may have more to say on the matter but as far as legality is concerned this is not an issue.
Think about it. The CAA has no interest or oversight on aircraft that are grounded/not airworthy which includes several big'uns with four Olympii or a couple of reheated Avons and often "taxi" at 200mph on nice sunday afternoons. No one has a licence to "operate" these as none exists. They are not deemed to be in flight due to the reference Beagle gave.