Nine months later both Houses of the Swiss Parliament awarded a concession for a railway, not only linking Aigle, Le Sépey and Leysin but beyond, to Les Diablerets, Pillon and Saanen.

However, following a new series of projects and concession applications, on 23 May 1905 the Berne Government finally approved the construction of a line between Aigle, Le Sépey and Les Diablerets on the left bank of the Grande Eau.

At the same time, a Westinghouse system replaced the existing braking equipment so enabling the rolling stock to travel on the Chemin de fer Aigle-Ollon-Monthey-Champéry line.

In 1975 the four local railway companies, Aigle-Leysin (AL); Aigle-Ollon-Monthey-Champéry (AOMC); Aigle-Sépey-Diablerets (ASD) and Bex-Villars-Bretaye (BVB) formed Transports Publics du Chablais Operating Community (TPC).

In the mid-1990s, faced with greatly increased operating costs, the Canton of Vaud and the communities served by the railway petitioned the Federal Government to revoke its 1985 decision.