It may have solely served the transportation requirements of the Glasgow and South-Western Railway and its successor in connection with the carriage of workers involved in the ongoing maintenance and/or the major reconstruction of Mossgiel Tunnel that took place between 1925 and 1927.

[7] By the 1920s only minor infrastructure was present with the double track main line and one siding running off to a loading dock to the west.

[6] The gradient from Kilmarnock eased at Garrochburn Goods depot before a gentle descent into Mauchline following the passage through Mossgiel or Skeoch Tunnel.

[11] The goods depot at Garrochburn was opened by the Glasgow and South-Western Railway in the 1920s and closed on 4 October 1965.

A temporary signal box had been established to control the southern access to the tunnel during the relining, etc.