I have been traveling with Amtrak over 10 years now. When I first started traveling with them, tickets did not need to be reserved for a particular train. For example, if I had a ticket for Friday, May 9th and for some reason I could not travel that day, I could always use it another time. As long as it was in a six month period, that ticket could be used on any other train for that particular destination, even at a different time. After September 11, 2001, things changed. Now, all trains are reserved and your ticket can only be used for that particular time and day. This makes it a litte more inconvenient, but that is the rule and there is nothing that can be done about that.
Being that you need a ticket for the exact day that you are traveling, I have learned over the years to have my ticket way ahead of time. Many people pick up their tickets in the kiosk machines the day they are traveling. If I know I am going to be traveling in the future, I order my tickets way ahead of time. First of all, if you order ahead of time, you can get a good discount and they will be mailed to you. If you order the last minute, you are going to pay a very high fare, then you have to pick them up from a kiosk machine. It is more convenient if they are mailed to you, but the tickets must be ordered within 10 days of traveling.
Also, the machines can be broken the day you have to travel. I just had a recent experience. I had a ticket to travel one Friday night. I decided to travel the next day instead. Of course I could not use my ticket for Friday night, so I had to get another one for Saturday. When I arrived at the station, to my dismay, both kiosk machines were down. This gave me some anxiety. I did not have much time. I arrived at the station at 9:00 and my train was coming at 9:15. When I called Amtrak to tell them the problem, there was a long waiting period. At this point now, I was very nervous because I did not know if I could board the train without a ticket. The train was a little delayed to my benefit and I finally got through to customer service.
They told me that they would print a ticket for me at the next station stop. All the while, I was very nervous because I did not know if I had to exit the train in order to get my ticket. I did not know my way around Penn Station in New York City. Finally, the crew members took care of the problem, but I experienced enough aggravation on my part.
From now on, I promised myself that I will always have my tickets ahead of time to avoid all this hassle. That may mean for me to actually go to the station the day before and pick them up. No more will I wait until the same day that I travel. It was very stressful for me. Then, second of all, you save money by ordering ahead of time.