Overview
- TfL says the programme requires an extra £409m, driven largely by upgrades at the Northfields and Cockfosters depots.
- Overnight and weekend test running continues, with TfL stressing safety and reliability before passenger service.
- Engineering work includes software and braking changes, retrofitting traction cables, and validating a new driver camera system.
- The rollout plan is being reprofilled, delaying the retirement of the 1975 trains and pushing back earlier targets for full fleet introduction.
- Passengers face planned closures between Acton Town and Heathrow from May 28–31 and a limited service between Acton Town and Heathrow from July 30 to August 3.