On 8 May 2012 it was announced by the DfT that the entire fleet of 24 2-car Class 456s would transfer to South West Trains (SWT) in 2014, to be used in conjunction with SWT's fleet on London inner-suburban lines [REF].
The Southern services on the South London Line were withdrawn in 2012 and replaced by a new London Overground service, the East London Line, operated using new air-conditioned 5-car Class 378 units [REF].