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windycity
Yeap,OPT is also F1 and you are good to go..
1. Currently at OPT (which expires on June 2009)--Since OPT is also an F1 status,he can take another I-20 from any US university and he can enter in his exsiting VISA..if OPT expires in June and he does not leave country within 60 days of expiry and also do not get admission to any college,University,his VISA will be void..Unless and until he maintains D/S,his F1 VISA is still valid..
2. Applying for admission for Fall 2009 (which is Sept 2009). Suppose you got admission on March-April 2009. ---if he leaves country in Valid OPT period,He will be fine..
3. Suppose new college issued I20 on April 2009. Here all your OPT/Visa all will be canceled and you will be in new F1 status. You will be in legal status as long as you maintain your F1 status and you don't have to apply for Visa if you don't leave the country.---yes,As soon as you take I-20,your OPT get expired but you will still be in F1 status--so you will not have to apply F1 VISA to enter USA if you already have VISA valid for that period..
4. Suppose you went to Nepal on April-May. You need to "APPLY FOR NEW VISA".
-No
*I am not a legal expert,please verify it with your international advisor*