Digital signalling work is being carried out, meaning several services will be replaced with buses.

Govia Thameslink Railway says the maps will allow people to gain more confidence at some stations.

Thameslink and Great Northern said their services will be cancelled or revised on Saturday.

Govia Thameslink Railway wants to recruit people and teach them how to maintain its fleet of trains.

Govia Thameslink Railway operates Southern, Thameslink, Gatwick Express and Great Northern services.

Multiple routes would be disrupted until the end of service on Saturday, the operator said.

In total about 1,000m (3281 ft) of cable is due to be replaced, Network Rail says.

Disruption continues after a railway blaze affected a gantry for overhead lines.