Take a look of this V fare rules.

There are lots of surcharges applied to specific dates. But on the penalty / change part of the rules, it says Unused Ticket is wholly refundable.

http://matrix.itasoftware.com/cvg/di...1991&J=2&AAD=0

Penalties:
NOTE -
- TICKETS MUST BE REISSUED WHEN ANY VOLUNTARY
CHANGE IS MADE.
.
1. WHOLLY UNUSED TICKETS -
CHANGES TO ORIGINATING FLIGHT -
WHOLLY UNUSED TICKETS ARE FULLY REFUNDABLE.
CHANGES ARE PERMITTED AT ANYTIME.
IF CHANGE IS MADE TO ORIGIN/DESTINATION/STOP-
OVER POINT/BOOKING CODE OR CHANGE VIOLATES
RULES OF ORIGINALLY TICKETED FARE-TICKET MUST
BE REPRICED AT CURRENT FARES APPLICABLE TO
CHANGED ITINERARY. CHANGES MUST BE MADE AND
TICKET REISSUED BY THE ADVANCE PURCHASE OF
THE NEW FARE.
A. IF NEW FARE IS HIGHER IN VALUE -
COLLECT FARE DIFFERENCE
B. IF NEW FARE IS LOWER IN VALUE -
THE RESIDUAL AMOUNT WILL BE REFUNDED TO
ORIGINAL FORM OF PAYMENT.
2. WHOLLY UNUSED TICKETS -
CHANGES TO OTHER THAN THE ORIGINATING FLIGHT
WITH NO CHANGE TO ORIGIN/DESTINATION/STOPOVER
POINTS -
CHANGES TO OTHER THAN THE ORIGINATING FLIGHT
MAY BE MADE ANYTIME WITHOUT REGARD TO THE
ADVANCE PURCHASE REQUIREMENT PROVIDED CHANGE
MEETS ALL OTHER RULES OF THE TICKETED FARE
AND ORIGINAL BOOKING CODE IS AVAILABLE.
IF CHANGE IS MADE TO ORIGIN/DESTINATION/
STOPOVER POINT/BOOKING CODE OR CHANGE
VIOLATES MIN/MAX REQUIREMENT OF ORIGINAL
TICKETED FARE - TICKET MUST BE REPRICED USING
CURRENT FARES APPLICABLE TO CHANGED
ITINERARY. CHANGES MUST BE MADE AND TICKET
REISSUED BY THE ADVANCE PURCHASE OF THE NEW
FARE.
A. IF NEW FARE IS HIGHER IN VALUE -
COLLECT FARE DIFFERENCE.
B. IF NEW FARE IS LOWER IN VALUE -
THE RESIDUAL AMOUNT WILL BE REFUNDED TO
ORIGINAL FORM OF PAYMENT.