No, they don't normally follow beacons, though there are back up procedures involving various beacons that can be used in the event of radio failures. Instead the Air Traffic Controllers normally give what are know as "radar vectors" once the aircraft leave the hold - i.e. headings to steer, which, combined with speed and altitude instructions should
end up with a nice procession of aircraft down the final approach to the in-use runway at Heathrow.
Usually you do indeed fly a S shaped pattern off Lamborne if landing to the West at Heathrow but if it's not busy (e.g. early AM arrivals) then you'll get some sort of short cut - and the controllers can and do vary the routing depending on traffic....