谢谢8老师，我是用新的i20签证的，用的新签证进来的美国，但当时海关查了我旧i20和新i20，所以才放行的，这样我是算用新的i20进来的还是用旧的进来的？
另外，如果我当时办得transfer，用的同一个sevis number，我用新i20进来时，仍然需要遵守30天的规定吗？
-Yes, the new I-20 is for your new study program, not continutiy of your old study program which you have completed. Obviously the CBP officer allowed you to enter US because you showed him/her your old I-20, otherwise, you would have not be allowed to enter US because your new I-20 effective date was > 30 days later at that time. You may talk to your school international student office that you used the OPT I-20 to enter US because the new I-20 was not effective at that time, so your OPT was still effective after you reentered US and your work was legal.
