Multiple saved flights

I'm flying the DC-3 cargo (8th ed.). I've created several different flights and saved them all. What I have discovered is that when I create a new flight, it has the properties of the last one I saved (e.g., same fuel load). And apparently if you create a new flight with the same aircraft, and change the parameters (e.g., fuel load) this will translate to any other previously saved flight you later open. Hope this isn't true, but has anyone else experienced it and does anyone have a workaround for it? Thanks.