Study visa to tourist viaa

Hi there

I will be studying very briefly in china (the program is from June 16-July 22) in Shanghai. The school will be sending me a letter with that as the time period. Therefore I am unsure what time frame I will get for my visa. If it is only those 35 days, is it possible to convert my study entry permit (X2 Jw202) to a L so that I can spend more time in china? Has anyone studied in china for less than 180 days but still was given the x2 with 180 days?