Construction of the main external structure will now start in May and take around six months to complete. It will be followed by an internal fit-out of the main passenger facilities, office and service areas.
The project is intended to improve capacity at the station and provide better facilities for passengers.
The scheme is the first phase of Network Rail’s plans for the station area, which include building a 28,000 sq m commercial scheme known as the Station Gateway and a 1270 space multi-storey car park.