I am a F-1 student right now. This winter holiday, I went back to China to visit my parents and got the visa back to US on Jan, 26, 2005(Which means I can go back to US before July, 25, 2005). However, due to my father's health situation, I decided to stay in China for several months. According the INS rules, I must be a full-time student in order to keep my F1 status. This is impossible right now because I am in China. Therefore I decided to extend my F-1(my old F-1 will expire in August, 2005). My new I-20 is in process by international student office right now.
My question is: I got my visa by using old I-20, but my I-20 should be the new one when I enter US. Will this cause trouble? Will the port officer check this? I can show both my old and new I-20 when I arrive US. But due to the visa application difficulty, I really don't want to apply for the visa using my new I-20 if I don't have to.