If I understood the term "positioning flight" I might be of more help. It sounds kind of like a deadhead sort of thing.

<< To put it simply, a positioning flight is a flight purchased for the sole purpose of getting you to another airport to start another trip, whether it be to lessen the cost of a trip or to just get you where your airline of choice will be flying from. >>

This makes sense but you make it sound like you want to go back to where you started.