Upvote:12
Nope, you haven't. You're good. You're in status until January 20, 2018. US visa expiry dates are for entry only. Your I-94 or the passport stamp will indicate until when can you stay in the US legally.
What the Visa Expiration Date Means
The visa expiration date is shown on the visa along with the visa issuance date. The time between visa issuance and expiration date is called your visa validity. The visa validity is the length of time you are permitted to travel to a port-of-entry in the United States.
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Admission to the United States and your Duration of Stay
Upon arriving at a port of entry, the CBP official will determine the length of your visit.
On the admission stamp or paper Form I-94, the U.S. immigration inspector records either an admitted-until date or "D/S" (duration of status). If your admission stamp or paper Form I-94 contains a specific date, then that is the date by which you must leave the United State. If you have D/S on your admission stamp or paper Form I-94, you may remain in the United States as long as you continue your course of studies, remain in your exchange program, or qualifying employment. The admitted-until date or D/S notation, shown on your admission stamp or paper Form I-94 is the official record of your authorized length of stay in the United States. You cannot use the visa expiration date in determining or referring to your permitted length of stay in the United States.
Source: U.S. Department Of State