While existing bookings do not earn points, if the flights today are the same price as when booked, I could cancel my existing and re-book correct? It would be via flight funds though, but was originally paid via credit cart (revenue earning). What if I instead just change the flight, selecting the same flight in the process, but now my "booking date" now has the new date, rather than my original booking date?

Just trying to figure it out to earn double on my existing flights, as I have two round trips during this time, and the prices are the same for all of them.