a single track. Automatic signalling conversions resumed in July 1958 with the section from Box Hill to Blackburn, followed by Mitcham to Ringwood in September of that year, and Blackburn to Mitcham in November 1960. Hawthorn to Camberwell was triplicated in December 1963, and the triplication was extended to East Camberwell in November 1964. Richmond to Burnley was quadruplicated in 1966/67, and triplication was extended to Box Hill in December 1971, followed by Burnley to Hawthorn in August 1972. This left a short section of double track on the up side of Richmond, but this was quadruplicated with the construction of a flyover in 1973. Ringwood to Croydon was converted to automatic signalling in November 1973 and duplicated in June 1984. Mooroolbark to Lilydale was converted to automatic signalling in June 1985. The Comeng trains were introduced to the Melbourne railway system in 1981. Initially, along with the Lilydale line, they were only allowed to operate on the Alamein, Belgrave, Dandenong and Glen Waverley lines, due to the width of the trains (). 21st century Future Level Crossing Removals The level crossing at Heatherdale Road, Mitcham was removed in 2017 along with building the new Heatherdale Station. The crossing was removed by lowering the line under Heatherdale Road. The station was rebuilt on the east side of the road. The level crossing at Blackburn Road in Blackburn was also removed in 2017, with the rail line lowered under Blackburn Road. The project included major enhancements to the existing Blackburn Station for better integration with Blackburn Village. A new walking and cycling path between Blackburn and Nunawading was built. The level crossings at Union Road, Surrey Hills and Mont Albert Road, Mont Albert will be removed along with the level crossings at Manchester road, Mooroolbark and Maroondah Highway, Lilydale. Network reconfiguration In the PTV Network Development Plan, released 2012, duplication between Moroolbark and Lilydale was proposed along with a new intermediate station. Network and operations Services The Lilydale and Belgrave lines are notable for a variety of express services. Weekday services run express between Richmond and Box Hill between 6 am and 7 pm on weekdays, with most express services making stops at Glenferrie and Camberwell stations, and some stopping at Surrey Hills station. Express trains are supplemented by Blackburn services stopping all stations between Richmond and Blackburn, with a select number of these services skipping East Richmond and Laburnum. A