How many days before the program starts can one enter China?

Hello, my name is Erwin and I am applying for the X1 visa in August to study in Beijing for one year from September. I would like to ask whether I could enter China a couple of weeks before my program starts. My program starts on September 11th, so would it be possible to enter China end of August? If not, what is the maximum time span one can enter before starting the program? Thank you for your time!