Replying...
Intro. As the time periods in England and Britian changed, the main railways were losing a lot of money due to heavy matinance needed on steam locomotives. So in the 50s to 60s, the Diesels were introduced into British Railways and were beginning to take over the railways, dominating any competitors in the steam era, and the mainland became a huge threat to all steam locomotives, as many began to be scrapped in exchange for engines like the BR Deltic Class, or BR Class 27s, while Sodor became both a heritage and a sanctuary for the railways. Following this time period will be the year 1959, when the last of the express steam locomotives on the mainland are replaced...Gordon's brothers from the LNER, and how many engines began coming to Sodor for safety and peace of mind.

Sodor: 1960s

@Vermont Von Sarac Marotan