I am a pre-school education major in China Normal University. I suggest you take the self-study exam while studying in a junior college. Those are two completely different experiences. Studying in junior college can help you to know your professional knowledge and background better and more systematically.

It will take some time to take the exam, but it depends on your personal self-control and mastery. Generally, few people have been in our school for three years. 4-5 years is common.