well bond,,the thing is you will still be in F-1 status even after you have OPT,,but the OPT period is given to you for your optional practicle purpose, and once you leave USA, they think you have completed your study and decided not to have the praticle training, and wont let you come back in. i understand what you are confusing about, what if you are in opt and your visa is already expired...or still have a valid visa.....right? it doesnt matter! a very important thing is ,,dont believe 100% what the staffs working in international student services say....they might be intern, or not immigration specialist..so,,its really good to talk with immigration layer,,they wont charge you anything,,just tell them im gonna take you to process my H1B but i wanna go to nepal now, can i do so or not..you will be given a solid suggestion for free. but his suggestion will be no! dont leave the country if you wanna come back. (after issuing OPT card, before having h1b status) this is how my attorney suggested me. or if you still dont understand,,then see this: OPT status

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