Sandown Park?
from The Guardian
"...A mass meeting of BA flight attendants at Kempton Park Racecourse later today..."
Sky News
"...More than 1,000 BA flight attendants met at Kempton Park Racecourse to debate the need for a new strike poll..."
The 4X4 flying red Unite flags I saw this morning going through Twickenham certainly seemed to be heading for Kempton Park. It was a long way off course for Sandown Park.