Commuters should brace for several weeks of public transport misery in and around Melbourne as the state government embarks on another school holidays “building blitz” on its transport upgrade projects.

There will be disruption to train services on the Frankston, Mernda and Sandringham lines while Gippsland commuters are being offered free travel as yet another round of upgrade works interrupts their journeys.

Commuters are in for more transport misery. Credit:Craig Abraham

Acting Premier Lisa Neville and Public Transport Minister Melissa Horne were in Kensington on Friday morning, where one of the Metro Tunnel entrances is being built, saying school holidays were the least disruptive time to get the work done.

Buses will replace trains between Caulfield and Flinders Street on the Cranbourne, Pakenham and Frankston lines from July 6 to July 14, extending to Westall and Moorabbin on July 13 and 14.