I've never seen that happen Claude, and I can't imagine that CSX would even permit Amtrak to run "an extra" train. Not to metion that Amtrak would need to find additional operating crews, something that's not all that easy to do; extra P42's that Albany doesn't have; and it would be breaking its promise to the Boston sleeping car passengers about meals in the dining car. And the NY section would have no cafe car for all the coach passengers, also not good.
Finally, as I mentioned before, this isn't the first time that I've seen different times. I'm not sure what causes it, but it happens all the time.