This is a PRIVATE road run of RT/RF/RM-family buses. Details are provided for the benefit of photographers.
Details from the LOTS website:
From Hyde Park, North Carriage Drive at 14:30, via Park Lane, Piccadilly, Haymarket, Strand, Aldwych, St Paul's, Cannon Street, London Bridge, Borough, Great Dover Street to Mandela Way. Return is optional via Tower Bridge, Lower/Upper Thames Street, Victoria Embankment, Westminster and Lambeth Bridges, Millbank, Tothill Street (by 55 Bdy), Hyde Park Corner back to Marble Arch.