I have already the Chinese visa "Z" single entry which one has to be converted within one month in a valid visa of one year.

I wonder what happens if I don't show up within one month in The school. I know I have to go out from China. Can I redo again my visa "Z" in HongKong or else? because I want to visit some friends in Shenzhen and other cities, at the same time I want to relax before going to my destination.

Robert