I googled it and a guy runs a bus list with makes and depots. I found one of these buses on the list, working out of Glasgow. Might be worth giving first a call to see if they can give you any route information. https://www.google.com/url?sa=t&source=web&rct=j&url=https://ukbuses.co.uk/fleet/firstglasgow.pdf&ved=2ahUKEwiOzPKNo_LxAhV9hP0HHVS2C-8QFjABegQIIRAC&usg=AOvVaw0eavS-nTzoAjJGcu8LBbv_