The immigration laws treat the adult, unmarried children of citizens differently than the adult, unmarried children of lawful permanent residents. Adult, unmarried children of U.S. citizens are placed in category F1 for family based visas (not to be confused with F1 student visas, a totally unrelated area of the law). Adult, unmarried children of lawful permanent residents are placed in category F2B.
Whenever an immigrant visa application is filed, a priority date is assigned. Think of a priority date as a line number.
Adult, unmarried children of lawful permanent residents v. adult, unmarried children of citizens
Sometimes, the priority date for adult, unmarried children of U.S. citizens (F1) is behind the priority date for adult, unmarried children of lawful permanent residents (F2B). For instance, in the January 2015 Visa Bulletin, the State Department reported the processing of visa applications for the adult, unmarried children of LPRs (for all countries other than Mexico and the Philippines) with a priority date of April 1, 2008. But the agency was processing visa applications for the adult, unmarried children of U.S. citizens bearing a priority date of July 8, 2007. This means that the adult, unmarried children of LPRs are getting their visas about 9 months earlier than the adult, unmarried children of U.S. citizens.
The reason for this discrepancy is the cap on the number of available visas for each type of category. The line is longer for adult, unmarried children of U.S. citizens than it is for adult, unmarried children of lawful permanent residents.
What happens if the sponsor naturalizes?
Our office is frequently contacted by sponsors of immigrant visas for their adult, unmarried children. These people are considering becoming U.S. citizens but worry what would happen to their child’s place in the visa line. They worry that moving their son or daughter from F2B to F1 family based visa category will slow down their child’s case. Naturalization of the sponsoring parent automatically converts the F2B application to an F1 classification.
Luckily, the law allows a 2B son or daughter to opt out of transfering to the F1 preference category. This is achieved by filing a formal request with the USCIS office having jurisdiction over the case. The adult, unmarried child will be allowed to retain the original 2B priority date, assuming that the I-130 was properly filed. Section 204(k)2) of the INA specifically allows for the alien beneficiary to opt-out of the automatic conversion to F1 classification. This allows the beneficary to retain their original priority date.
USCIS has issued a memo which addresses this issue.