You are doing awesome for someone who started last September! Nice job! So one thing you might try, is going into butterfly from a solid outside leg hang. You have to kind of push yourself up into butterfly, but the knee hook is pretty solid from that move and your body will be closer to the pole as well so you can hold your butterfly longer without too much effort once you get in position. And play around with lines, you can have your back leg straight.. but just remember to keep the whole line active and keep pushing that leg down to the floor :)