In case anyone is interested TfL have put forward a paper seeking authority to purchase 9 more Class 710 EMUs. 3 will be to 4 car configuration and 6 to 5 car configuration (a new variant for LO).

https://tfl.gov.uk/cdn/static/cms/do...nda-item11.pdf

The plan is that 2 of the 4 cars are for the Barking Riverside service. The planned 1 unit on the Romford - Upminster line would be replaced by a class 315 (!) being held back for that service. This unit and the other new 4 car unit would go to the Watford service to displace two class 378s to the ELL route. The 6 5-car class 710s would be put on the NLL/WLL route to displace an equal number to the ELL. The ELL would thus have an increased service level of 20tph.

In the paper TfL say they are seeking external funding for the signalling and track enhancements necessary to run the improved ELL service.

Debate on another forum has suggested the numbers of transferred units from the Watford line "don't make sense". I confess I'm not knowledgeable enough to comment on that - I'm just reflecting what the paper says.

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Paul C
via Google