I have a question about changing Classic tickets. I booked a return trip and I want to change the data of the second leg. The first leg is already this weekend, but the second leg is only in January. I just asked customer service how expensive the change would be, and the price they want is outrageous. I suspect they reprice the entire ticket and because the first leg is so close in time, the entire ticket (and therefore the fare difference) is incredibly large. The fare difference is more than booking a new one way J fare for the second leg.

What happens if I wait until after my first leg completed to change the date of the second leg? In this case, they can only reprice the second leg, and it should come out cheaper? Do I understand this right, or is there a flaw in my logic?