Originally Posted by sapman986
I'm going to take a shot in the dark here and guess that they did not use online check in before the scheduled departure of the trains. I doubt CO would cancel the air segments if you had already checked in.
Online checkin doesn't check you in for the Amtrak segments. I know for a fact that one of the people with problems used online checkin. The problem wasn't with the immediately following Amtrak segment, it was with the return.