Improvising study four

Dave I have been playing the examples for improvising study four. Even though I cant play alot of them, I have listen to all of them alot. In your video, you explained that it could take two years or more to get a handle on the examples. You also said that we should keep going back to them to pick up a couple more each month. I still go back to some of my study songs, so I know what you mean. My question is...............Can I move on to study five? I DONT WANT TO ASUME ANYTHING, AND i JUST WANT TO DO MY LESSONS IN ORDER. tHANK YOU DAN