It is April 25th, 1971 and Amtrak will appear on May 1st, bringing an end to most privatly operated long distance passenger trains in the United States.
The Truckee Limited, a charter by PLA, was supposed to pick up passengers at Richmond, but confusion in their orders let the special pass thru Richmond without stopping. The SP's San Joaquin Daylight would be following and they picked up the stranded passengers taking them to Martinez to transfer to the excursion.
At this point, the special has pulled up the main line toward the bridge and the San Joaquin Daylight is taking the switch to head down the Moccoco to Tracy and the Central Valley.