I am in US now. I just received the approval letter from immigration of my L1A application with new I94 form valid from Jul 26 2011 to Jul 25 2010 (1 year). I want to know what will happen if I leave US and come back within the periond of my L1A validity? Will the immigration withdraw my new I94 form when I leave US and ask for visa when I come back? My previous B1/B2 visa will expire in Nov 2011. Do I need to change my visa from B1/B2 to L1A if I have to leave US and come back later? Can I apply for the change of my visa in US? Or I have to apply for it abroad?
You don't need to do anything. If either one is valid, you are good.
if you changed status in the u.s. from b1/ b2 to L1A which it appears to be the case, your b1/b2 is effectively canceled. you cannot maintain 2 visas at the same time. if you did change status here in the u.s. to L1A after entering on b1/b2 and you exit the u.s. you must go to the consulate for visa stamping so that the new L1A is in your passport before you will be allowed to re-enter the u.s. the b1/b2 is already changed here in the u.s. but to re-enter the u.s. on it you must also get the change reflected in your passport with a visa stamp that says L1A.
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