Whats up with AutoTrain Fares?

[Henlady]

The current AutoTrain Fares for vehicles for Sept/Oct/Nov from Sanford to Lorton are higher ($182) than the southbound vehicle fare($140). In all our fall travels in the past, it has always been more expensive going south due to "snowbirds" traveling enmass on their southern journey. The Sanford to Lorton route up thru August 31st is $140 for vehicles and from Dec 1 it is again $140. Just seems a little strange.