Posted by: furke October 13, 2010
How long can you be out of country during F1 visa?
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Since your level of education changed from masters to phd, you must have a new I-20 to re-enter.
Yes, you can not be out for more than 5 months but it is true if you are on the same program and all info on I-20 remains unchanged and had your I 20 signed by your DSO on page 3 for re-entry. In your case, you need a brand new I-20.
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