If you are an F-1 student in "duration of status," on February 5 you might wake up having accrued 180 days "unlawful presence." That's even if, to your knowledge, you have never violated your status. Last August 9, a USCIS policy memorandum took effect changing the way unlawful presence is calculated. Prior to that memo, an F-1 student began accruing unlawful presence from the date of the USCIS finding of status violation. But as of August 9, USCIS began counting from the day of the violation itself. For those whose violations are found to have occurred before the memo took effect, unlawful presence began accruing on August 9, the memo's effective date. Let's take for example, a worst-case scenario, where an employer does not abide by its requirements, but the student is unaware. And example is an employer who does not adhere to a STEM OPT training plan. Upon the student's application to change status to H-1B, USCIS finds he violated F-1 status at the beginning of his STEM OPT and began accruing unlawful presence August 9, 2018. The student receives notification only when the change of status is denied in March 2019, having thus unknowingly accrued more than 180 days of unlawful presence.

There is a lawsuit underway challenging the new policy, but it will not protect those at risk. The Court scheduled its next hearing on the matter for March 26 but chose not to suspend the memo while the litigation is pending. That means the first day of unlawful presence for vulnerable students is still August 9, 2018; they will reach the 180-day mark on February 5. A period of unlawful presence that length triggers a "three-year bar" on re-entering the United States. A one-year period of unlawful presence triggers the "ten-year bar."

You may have received a denial of change of status; you may have responded to a Request for Evidence (RFE) alleging violation of F-1 status; or you may have received such an RFE but not yet responded to it. Different responses are appropriate to these different situations – consult an immigration attorney to determine the right course of action in your case.

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