Yes, you can upgrade an existing Amtrak ticket to a Roomette at any time prior to boarding, provided there is availability on your specific train. The most efficient way to do this is through the Amtrak mobile app or website by selecting "Modify Trip" and choosing a different accommodation type; you will simply be charged the difference between your current fare and the prevailing Roomette price. For those looking for a deal, Amtrak also has a "BidUp" program where passengers in Coach or Business class can place a monetary bid to be moved into a Roomette or Bedroom. If your bid is accepted, you'll be notified via email shortly before departure. Upgrading to a Roomette transitions you into Amtrak's "First Class" service, which includes private sleeping quarters with two seats that convert into beds, a dedicated car attendant, and complimentary meals in the Dining Car. You also gain access to station lounges like the Metropolitan Lounge in major cities like New York, Chicago, or Washington D.C. If you are already at the station, you can also inquire at the ticket window for "day-of" upgrade availability.