Refund on cancelled/changed tickets

[theslaz@gmail.com]

Don't know if this is the right place to be asking this, but here goes. If not, maybe someone could point me in the right direction. Flying to Vancouver on Friday to start a 14 day cruise out of Florida. Departing Prince George and arriving in Vancouver at 4:30 Pm. Our connection leaves at 7:30 P.M. We are afraid that we may no make that connection, theefore we thought we would catch an earlier flight out of Prince George . To do this we would have to cancel our present tickets with Westjet and purchase new ones. Does anyone know if WestJet would give us some credit from the old tickets, toward the new ones? Thanks in advance.