I just apply busines visa for my collecgue with all the supporting documnets, and china embassy only approved L visa for 90 days per entry. Actually what I need is F visa - 180 days per entry because I 'm going to send him for 6 month training in Shanghai. When he's in Shanghai, how to apply for extension for another 90 days? Does he need to go out China and then come back. Kindly advice.