Regarding today's visitors, I know nothing, but I am pretty convinced that the aircraft that arrived from Dubai this morning is related.
The aircraft is American registered to a bank that specialises in financing such machines, but after digging the last known 'owners' were an Australian company called 'Beyond Holdings', a mobile phone company.
As far as I can see the aircraft hasn't been to Australia for a long time, so the ownership may have changed, but it does kick around the Far East a lot, so it's possible that Dubai was a refuelling stop.
If RL's people are over, it was by scheduled flight, which I doubt. No private jets have come to the UK from 'obvious' Lerner originating points.