Engineering work is taking place overnight in the Alexandra Palace area, closing some lines. This means from 11.25pm until 5.10am each day until Friday morning, buses will replace trains between Alexandra Palace and Stevenage via Welwyn Garden City. Trains between London and Cambridge / Kings Lynn / Peterborough will run to a revised timetable, diverting non-stop via Hertford North, and have extended journey times. You can plan your journey using the National Rail Enquiries Journey Planner at nationalrail.co.uk/journey-planner. Be advised that replacement vehicles may be busier than usual, and you should allow extra time for your journey.