3.2 The LOTRAIN Project comprises [...] 45 new electric multiple units to support the following London Overground Programmes:
(a) Gospel Oak – Barking Capacity Increase (eight, four car trains);
(b) West Anglia Route (Devolution) Programme including Romford-Upminster, (31 x four car trains); and
(c) London Overground Frequency Increase Programme, which enhances the current eight trains per hour (tph) on the North London Line (NLL) to 10 tph and increased service resilience on the East London Line (ELL) (six, four car trains)...
{then explained later in the paper}
3.6 By putting new trains
{i.e. what we now know as the 710s} on the Euston – Watford line the existing Class 378 trains on that route can, in five car formation, be cascaded onto the NLL and ELL to provide a larger and homogenous Class 378 5 car fleet to deliver the planned tph increases.
http://content.tfl.gov.uk/fpc-20150617-item16-part-1-lotrain.pdf
. Mind you I am surprised that a five car electrostar is getting on for the same length as a Bakerloo line train. But then it does seem a long walk to the front of the train at Victoria (so I am nearer to the East Croydon exit).
.
