RDCs in Alberta ran up until 1985 between Calgary and Edmonton. But south of Calgary, "all Dayliner operations south of Calgary would cease on July 17th, 1971," according to
Galtrailway.com/2015/05/11/self-propelled-railway-passenger-transportation-in-southern-alberta

The Youtubers referenced are:
Luke Towan: https://www.youtube.com/channe....l/UCjRkUtHQ774mTg1vr
Ron's Trains N Things: https://www.youtube.com/channe....l/UCDIjWTVFM8adgHWDP
sparky107107: https://www.youtube.com/channe....l/UCzO7bPUz5QixrW9rC
Check out their channels.
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