Somewhere there was a note from the Perch Patrol explaining that it was being discontinued due to the uncertainty of the Amtrak schedule. It comes to freight trains have priority on the tracks over commuter trains. At times the trains are delayed for several or more hours.
I am sure you can understand the problems and headaches a late train can cause for the guides, lodging and transportation to and from the train depot and so on.
http://www.perchpatrol.com/express.htm