Work to replace level crossings in Edithvale, Chelsea, and Bonbeach along the Frankston Line have been held up due to legacy signalling equipment.
Buses will continue to replace trains until Monday, February 15, a week longer than originally scheduled.
The signalling equipment will be replaced once the project is complete, which involves removing five level crossings between Edithvale and Bonbeach and renewing Edithvale, Chelsea and Bonbeach station.
On the Hurstbridge Line, station designs have been revealed for the Greensborough and Montmorency stations.
The duplication of the Hurstbridge Line requires the stations to be rebuilt and the new designs include more vegetation and landscaping, better connections, improved facilities, more accessibility, and greater parking.
The new stations will be made safer through straighter platforms, which eliminate the gap between train and platform by removing the curve. Safety will also be increased through improved lighting and CCTV cameras.
The new designs reflect community feedback that prioritised native vegetation and modern, natural, and earthy tones for the built structures. The Montmorency station will remain at the heat of the local community.
On the Pakenham Line, work is stepping up on the Clyde Road level crossing removal.
Located in Berwick, a new road underpass is being built beneath the rail line.
Piling is currently underway, with 300 piles drilled up to 29 metres deep for the road underpass and rail bridge.
Buses will replace trains between Friday, February 19 and Friday, February 26 as a construction blitz sees work along the Pakenham Line.