Here are the scheduled Tube system repairs for this weekend.
Farringdon station is closed to all 3 Tube lines – Circle, Metropolitan and Hammersmith/City on Sunday.
Portions of the Circle and Hammersmith/City lines are closed on Saturday only. The non-Heathrow Piccadilly segment is shut, as well as part of the Northern line and London Tramlink all weekend. Disruptions on London Overground are only on Sunday.
London transport will be affected by the London Marathon on Sunday. Given the events that occurred in Boston this past Monday, it’s probably wise to check this info frequently and maybe still assume that there will be unannounced security-related changes.