The changes you can make are free of cost if you keep your flight dynamic at a gap of 24 hours prior to booking your flight. Air Canada's Modified Flight Policy allows all passengers to make some modifications to their flight if necessary. If you are a dynamic Air Canada Airlines Change Flight at the airspace or Air Canada ticket workplace, the Air Canada Airlines reserves the right to make changes to the administration fee. If you have modified the moment of your flight at the time of ticket fetching within 24 hours of booking, you may not be charged any fee to activate your flight. However, you want to pay the fare difference, if any. You will also be able to request a full refund if your flight is canceled irrespective of the fare category. This additionally applies to the type of fare, a number of tickets, and other categories.