If I go to china with tourist visa how can i change it to X type?

Dir sir/madam,
I applied to chinese language programme and major programme in China university.They accecpted my application and they asked me original non-criminal police record with china embassy stamp. I sent that one also. They told me we will send JW202 form within 50 days then you can apply "X type" in your country but that 50th day is coming on middle of march but my language programme will start on march 4. They informe me "you have to come and register on march 4. If you miss that your programme will canceled. So I have to go to China and register on march 4th. So what type I can apply for go to China. Can i go with L type? If I go with L type how can i change it to X type?