回複：謝謝8老師，還有一個疑問 回複：回複：代友請教：急請問各位老師這種情況身份違例嗎？謝謝！

謝謝8老師，我是用新的i20簽證的，用的新簽證進來的美國，但當時海關查了我舊i20和新i20，所以才放行的，這樣我是算用新的i20進來的還是用舊的進來的？

另外，如果我當時辦得transfer，用的同一個sevis number，我用新i20進來時，仍然需要遵守30天的規定嗎？

-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.