Originally Posted by
Calchas
1. If you make no changes to the first flight coupon (the first flight), you pay the delta in any taxes, airport fees and airline surcharges, plus any increase in the fare. If you are changing the ticketed points or the first flight coupon, then in addition to that you pay the 125 USD fee.
If you are only changing dates/times/carriers, and the first flight remains unchanged, then you do not pay the fare difference. Only difference in taxes and airline-imposed fees.
See my added emphasis in the rules:
Code:
CHANGES BEFORE DEPARTURE
A/ CHANGES ARE PERMITTED PROVIDED TICKETED POINTS
REMAIN THE SAME. IF THE FIRST FLIGHT COUPON IS
BEING CHANGED AND THE FARE LEVEL HAS INCREASED
SINCE THE TICKET ISSUANCE THE DIFFERENCE BETWEEN
THE OLD AND NEW FARE BE CHARGED.