Looking at Lewes in close up, Google Earth claims that the Greenwich Meridian runs through the Black Horse, when - as any fule kno - it runs close to, but not exactly, through the Meridian PH.
If this is the same technology that is used for precision bombing Osama bin Laden and his friends, then no wonder he hasn't been hit yet. It's about 50 metres off target.
Could well be before 99/2000 with the seats removed for the Golf or something similar. They must use shots taken during the summer to get the best view.