Caption: After receiving their written clearance onto the Occupancy Control System (OCS) part of the Galt Subdivision, CPKC train no. 529 eases to a stop at the East Siding Switch Puslinch. Their clearance from J.D. read "clear main track". As RTC has no control over the signals and switches, the conductor will get out and use a pushbutton to activate the switch. Once its in position they'll get a restricting signal into the unsignalled siding. After the last car clears the switch will automatically return to normal and return to clear signals for the train they're meeting. This system has been around for decades and is slowly being upgraded to CTC in nearby areas. Soon written instructions will be a thing of the past. For now it's great for listening in, getting info for trains and meets. Soon this will be a bygone era in the new age of railroading.