Glynn, great to see you back modeling these nice planes for all of us! You really are one of the best 3D artists in IL-2 world!
Don't worry about Jetwar versions, just release the version that works for you in Jetwar 1.1 and go on creating these great planes. I'm sure there are several Java modders willing to help you, ready to convert your planes for Jetwar 1.2 and create slots for your new planes both for Jetwar 1.1 and 1.2. Thanks to the Crusader, Phantom, MiG-19 etc. projects there are now more modders familiar with the Java and FM side needed to make your great models work well in game.