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If a J-1 student has transferred to UT from another school and therefore has a different program date, program number, or sponsor listed on their visa, they must apply for a new J-1 visa before returning to the US.
Travel to Canada, Mexico, and adjacent islands (except Cuba)
F-1/J-1 students are permitted to re-enter the US after a single visit of no more than 30 days to a contiguous territory (Canada, Mexico, and adjacent islands) without having to obtain a new visa prior to re-entry. This rule, known as Automatic Re-validation of Visa, even applies to F-1/J-1 students with an expired visa.
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