After 1878, the Freycinet Plan called for standard gauge 'local interest lines' be integrated into the national network prior to nationalisation. The stated was objective was to allow the local lines to be operated by the major companies. Mr. Mangini, the founder and director of the DSE, signed the contractual agreement to do this in 1881. This contract included the construction of the rest of the line, now classified of 'national interest', to Bellegarde. This section, completing the line, was opened on 1 April 1882. On 26 May 1883, the DSE signed the sale of the line to the PLM, with an effective date of 1 January 1884. Finally, the DSE was wound up on 23 January 1884. In 1886, the Andelot to Cluse line connected it to the Dijon to Lausanne artery.