I submited a petition requesting change of status from H1 to F1 before I got laid off. My case was not adjudicated before the school registration deadline of this semester (Jan 07 2009). Therefore, admission office deferred my admission to next semester and I sent new I-20 to USCIS. All of a sudden, the petition was approved on Feb 09 2009 (the date on I-94). The begin date on I-20 is however April 06 2009. In this case, can I legally stay in US until the new semester starts? If yes, shouldn't I maintain fulltime student status from Feb 09 to April 06 (I can not register for this semester anymore)? What should I do?