The Board of Immigration Appeals has determined that when a “U nonimmigrant visa is not immediately available to a respondent and the record does not establish that one is likely to be available in the reasonably near future, administrative closure over DHS’ objection is inappropriate.” The Board further noted that a six month period of administrative closure is presumptively reasonable.
The full text of Matter of Ibarra Vega can be found here: https://www.justice.gov/eoir/media/1429421/dl?inline