The first four are intended to open early next year at Cockfosters, Northolt, Hillingdon and Hounslow West stations.
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2.
The Piccadilly line is operating a shuttle service between Heathrow terminals and Hammersmith, and between Arnos Grove and Cockfosters.
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3.
Nine lines ran limited services, while the Piccadilly line operated a shuttle service between Heathrow terminals and Hammersmith, and between Arnos Grove and Cockfosters.
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