How long it takes to get to the next belt rank is completely up to you. Most people that practice the self discipline to make it to Black Belt will take somewhere between 4 and 8 years. Some people may move faster and some may move slower. That is irrelevant. You are here for your own individual growth with no comparison to anyone else in the school. I will push you to achieve your best performance and gain as much out of your training as possible. But remember, you are still the one that has to do the work. The only way to see substantial growth is to push yourself outside of your comfort zone.