I did check actually and they are asking to have two officials there to monitor the record attempt, so you'd actually need to have a crew with you, support cars etc.
Some of the records require officials be present, some of them will validate without if you can provide enough evidence. Obviously going for a year record or month record normal people can't afford to keep a GWR rep around.
LEJOGLE is only a GWR, there is no RRA record for it. I'm not sure about UMCA but you could check on their site.