Sub Range Question in TMO

[tomoose]

I was playing the other day and set my course to Midway for the usual refuelling en route to my patrol station. I'd plotted in my course from Pearl to Midway to Okinawa. I put the TC on and subsequently got distracted so that when I got back to my screen I found the "refuel/rearm?" screen prompt but my sub, because of TC, was well past Midway and well on it's way to the Okinawa area. So when I clicked on "refuel/rearm" I got the filled tank well after Midway thereby saving a large dose of fuel if you see what I mean. I didn't intend it this way but I guess it's a wee bit of a cheat to save fuel. At least that was my perception, can anybody else verify this or did I misperceive what happened?