My advice is to get it in as early as possible. It betters your chances for acceptance, saves you a lot of waiting and anxiety (don't need anymore of this than you already have), and it also may save you a lot of money (it probably saved me close to ten grand because I got an acceptance so early I canceled a lot of my interviews). Applying early is huge, and september is pretty late in the process, I had five interviews in September. BUT and here is the big BUT if you can't do anything about it because of cirqumstances, then you have to do what you have to do. In that case don't fret and make do with what you have. I hope that helps, let me know if you have any other questions.