Passengers on the Barking to Gospel Oak line have become used to delays and disruption in recent times.

And while many would have hoped that would come to an end with the planned introduction of a new fleet this month, there’s yet another problem affecting the troubled route.

Transport for London has confirmed that the Class 710 trains - set to carry almost 700 passengers on each - will now not be arriving until much closer to Christmas.

Rory O’Neill, TfL’s general manager for London Overground, apologised for the delay, explaining it was due to manufacturer Bombardier needing to do further software development.

He said: “Safety testing for the new electric trains is now well underway and Bombardier has said that they should be ready to enter passenger service in the second half of December.

“We share our customers’ frustration about this and are fully focused on ensuring the trains are delivered as quickly as possible.”

He also explained that the existing diesel trains were becoming “increasingly unreliable”, adding: “To increase the likelihood of a reliable weekday service, trains will run less frequently at weekends until the new trains begin to be introduced.”

The 54-strong fleet of high-tech trains, featuring air conditioning, walk-through carriages and WiFi, is set to roll out across the Overground network over the next few years, replacing those which have been in use for more than 35 years.

The Barking to Gospel Oak line will benefit from the first eight of these, doubling capacity on the route.

Preparing the line for the new trains has not been without its problems, with passengers disrupted by regular weekend closures as well as others that shut the route for several weeks at a time.

It was closed between June 2016 and February 2017 for electrification work to be carried out, but delays meant that further line closures were necessary to complete it.

This meant that the original roll-out date for the new electric trains - summer 2017 - could not be met.