Like Ken said, the time frame varies greatly and just should not be rushed. I know that is not your intent either. Frequent training sessions and multiple flights per day help a lot too. It imbeds habits and doesn't give you a chance to forget things. When I took full scale flying lessons, I saved money until I was able to fly at least 4 times/week. This really sped up the learning process and works with RC planes too. Stick with it and you'll get there.