Just remembered about this thread.
Piccadilly line should be running on 26th Dec.

"
Special services will run on all lines. First trains will run from about 07.45 with last trains at normal Saturday times. Sunday service levels will operate. Exceptions are as follows:-
No London Overground service.
Central line:
A reduced service will operate between Ealing Broadway and White City due to Network Rail engineering work.
Hammersmith & City/Circle lines:
No Hammersmith & City Line service between Hammersmith and Barking. No Circle Line service between Hammersmith and Tower Hill via King’s Cross. A special Circle Line service will operate between Edgware Road and Barking via Victoria.
District line:
No service between Earl’s Court and Kensington (Olympia).
Metropolitan line:
No service between Baker Street and Aldgate due to engineering work. No Chiltern Railways service.
Waterloo & City line: No Service"