alexis_lambert,
Departing Heathrow BA001 is scheduled off blocks at 1830L. If its ontime expect take off at the following times:
Runway 27R 1850-1900
Runway 09L 1855-1905
Concorde does not depart from 27L/09R
Arriving into Heathrow BA002 is scheduled to arrive "on stand" at 1800L but it could "land" as early as 1715L. Best check BAA or BA website for estimated arrival time.
Concorde will land on which ever runway is active for arrivals.
Hope this helps.