I-129F validity period is about to expire.
Generally speaking, this is not a problem. Consulates and embassies around the world are recovering from the delays caused by the COVID-19 pandemic and realize that it may have been impossible to schedule an interview within the 120-day validity period of the I-129F approved petition. Assuming the delay was not unreasonable and/or the client's fault, the consulate or embassy will generally extend the validity period of the I-129F petition for an additional 120 days. From a practice pointer perspective, you should have both the petitioner and foreign fiancé sign new declarations re-confirming that they are both still eligible to marry, and that they intend to marry within 90 days of entry into the United States on the K-1 visa. Although the Department of State has not expressly stated that it will re-validate, or extend the validity period in all cases, it does provide that “[a] Consular Officer can extend the validity of the petition if it expires before visa processing is completed.”
The fiancé entered on a K-1 visa, married within 90 days, but did not file an I-485 to adjust status within that period of time before divorce happened.
There is no requirement to file an adjustment application within 90 days – only a requirement to marry within 90 days. If the applicant does not file for adjustment within the 90-day period, then she will fall out of status and will begin accruing unlawful presence. See Matter of Sesay, 25 I&N Dec. 431 (Mar. 17, 2011). In this case the FN entered as a K-1, married the USC petitioner within 90 days, and did not file the I-485 until more than 18 months after her K-1 admission. The parties divorced before the I-485 was adjudicated. The BIA held: A fiancé(e) visa holder satisfies the visa eligibility and visa availability requirements of section 245(a) of the Act on the date he or she is admitted to the United States as a K-1 nonimmigrant, provided that the fiancé(e) enters into a bona fide marriage with the fiancé(e) petitioner within 90 days. Therefore, a fiancé(e) visa holder may be granted adjustment of status under sections 245(a) and(d) of the Act, even if the marriage to the fiancé(e) visa petitioner does not exist at the time that the adjustment application is adjudicated, if the applicant can demonstrate that s/he entered into bona fide a marriage within the 90-day period to the fiancé visa petitioner.
The fiancé entered the U.S. on a K-1 visa, but did not marry the petitioner within 90 days.
The K-1 visa is a nonimmigrant visa like any other nonimmigrant visa: it is for a very specific purpose, and it is for a very specific period of time. The specific purpose of the visa is to marry the I-129F petitioner; the specific period of time is 90 days. If the fiancé does not marry the petitioner within the 90 days, then she falls out of status. If the fiancé remains in the United States, she begins to accrue unlawful presence. The fiancé may not subsequently adjust status through a different spouse because she entered on a specific K-1 nonimmigrant visa. If the fiancé does not leave the United States and marries the I-129F petitioner beyond the 90-day duration of status of the K-1 visa, then she must basically start from scratch. The original USC petitioner would file a new I-130 petition, and the now married foreign national would file an application to adjust status. Although the foreign national accrues unlawful presence after the end of the 90-day duration of status, she has a lawful entry, is the immediate relative of a USC, and may adjust status to lawful permanent residency.