I booked my Thanksgiving travel (BAL-WBG) as soon as the dates opened in the reservation systems. The plan for our family gathering changed, and now need to take the train to NPN and then take the bus connection to NFK. Will it cause any problems to just book WBG-NPN-NFK and NFK-NPN-WBG segments separately?

If I cancel my existing reservation and re-book, I'll end up paying an extra $97. If I buy just the WBG-NPN-NFK and NFK-NPN-WBG segments, the extra cost is $63. I know that isn't a huge difference, but I'm on a graduate student budget.