This is more than three years late - the original plan was for the line to have been opened by the Queen in December 2018. The project is also more than £4bn over budget.
Under the revised plans from August last year, trains from Reading and Heathrow would not have run all the way through to Shenfield, at the eastern end of the line, until May 2023, and would instead have terminated at Paddington.
Now the aim is to run direct services to and from Heathrow and Reading to Abbey Wood by September next year, meaning passengers for stations in the City and at Canary Wharf will not having to change trains at Paddington.
This means the journey between the airport and Canary Wharf will take about 38 minutes – discouraging car travel and boosting TfL’s revenues, with airport passengers being charged a premium rate to use Crossrail.
When the line opens under central London next year, services will initially run between Abbey Wood and Paddington, at a frequency of 12 trains an hour.
Adding the Heathrow and Reading trains will increase peak frequencies in the central London tunnel section to 24 trains an hour.
Crossrail trains already operate between Reading, Heathrow and Paddington, and Shenfield and Liverpool Street, though they are currently known as TfL Rail.
The ability to run trains from Crossrail’s western branch through central London from September next year is being made possible by accelerating the integration with Network Rail timetables.
However through-trains to and from Shenfield will not start until May 2023. In the initial period after the opening of the central section, they will terminate at Paddington. There will also be a “reduced” number of trains prior to the full opening of the end-to-end railway.
A report to TfL’s Elizabeth line committee said: “The proposed changes have potential to contribute to minimising the costs of the Crossrail project in its later stages, as well as a potential opportunity to improve revenue.
“In addition, the introduction of through services from the west builds upon Government’s ‘Roadmap’ in supporting recovery from the coronavirus pandemic.
“Providing much needed public transport capacity and connectivity will be key in helping ensure that passengers, particularly in the Western and Thames Valley corridor, can access services and facilities which in turn supports economic growth and recovery.”
The changes effectively split Crossrail into two “separate but overlapping” railways in the interim – which it is hoped will make it more reliable, means fewer drivers and trains are required initially and should reduce the number of trains having to be “reversed” at Paddington.
Crossrail chief executive Mark Wild told the Commons public accounts committee on Monday that the earliest possible opening date for Crossrail was next February.
This is because “trial operations”, a process described as the “dress rehearsal” and using thousands of volunteers to test the trains and stations, will not start until November at the earliest and will take 10-12 weeks to complete.
However Crossrail chiefs remain concerned that any problems with the final upgrade of train software, due to happen around September, could lead to “months” of delays.
The committee heard the £18.9bn cost of Crossrail did not include the £1bn train fleet or the cost of the train depot, estimated between £250 to £300m – meaning the total bill exceeds £20bn.
Crossrail’s Paddington station is due to be handed over to TfL next month, with Canary Wharf station being finished in October – leaving Bond Street as the last of the nine new stations to complete.