From Monday 18th March the escalators from Platform 20 into the Underground will be closed for two weeks for maintenance.
Morning Peak: You should should use either the main exit from the International Terminal, or Platform 19, to leave the station and access the Underground.
Evening Peak: You should (from the Tube) use the main Tube exit and access the platform via the main entrance to the International Terminal or platform 19. If you arrive in the Peak Hour Subway you will be able to use escalators to platforms 21 & 22 and walk around. There will also be lift access to platform 20.