I had my own experience of this - I narrowly missed a flight from Marseille and went to the ticket counter to change my flight to the next day. The woman at the

I had my own experience of this - I narrowly missed a flight from Marseille and went to the ticket counter to change my flight to the next day. The woman at the counter checked my ticket and happily told me no she can't change it I will have to buy another. I told her that it was a marine fare and could be changed. She didn't look so happy then and said your travel agent needs to do it. Which they did.