Fin Question

I just picked up a 9" Flexie for my 7’2" egg, and because of the short box, the fin sticks out from the tail about 1 1/2 inches. How does this change the dynamics of the board design ? Am I, in a sense, creating a longer board? I’ve only ridden it in crappy conditions, so I haven’t really gotten a feel for it yet. All thoughts appreciated, Jack