QF mixed inflexible and flexible tickets refund conditions.

QF mixed inflexible and flexible tickets refund conditions.

Heading to the US at the end of the year for study and looking at flying QF. While I know the dates I'm flying over, I'm not sure of the return dates but I know they'll be outside of the 12-month ticket validity period. I'm wondering if I can save money by booking a return (due to one way fare mark up) but making it flexible on the return leg only and requesting a refund after the trip has commenced. Has anyone got experience with this? Thanks!