Passenger Trains > Flash Pass

My wife work for Amtrak and one of the perks is the Spouse get to have a Flash pass. I live in So Cal so I've ridden the Surfliner for trips to almost everywhere along the line for free, thank you very much. But I have question maybe Mundo and Janoff could answer or anybody else that knows. I remember reading somewhere I can ride almost any line like Long distance train but need reservation but what about San Joaquin is that consider a Long Distance train? Can I flash my pass on Ambus from Lax to Bakersfield to get the San Joaquin or does the pass only work on the train. Johnny

You should check with a ticket clerk, but my understanding is that its good on Bues and San Joaquins.