In the other direction to Pittsburgh leaves at 7:30pm and takes 4½ hours, more than 2 hours longer than driving.
I guess that's just how the panhandle panhandles.
The Amtrack website also mentions:
Known as Maryland's “Queen City,” Cumberland was an early gateway to the West. Today, it is a bustling arts center and popular stopover for cyclists using the trail network between Pittsburgh and Washington, D.C.