The Second Circuit has determined that the Board of Immigration Appeals' authority to take a late-filed appeal on certification is a discretionary determination, and thus, not reviewable by the court of appeals.
The full text of Vela-Estrada v. Lynch can be found here: http://www.ca2.uscourts.gov/decisions/isysquery/73af4a5d-25eb-468d-ad34-9bb571816aed/5/doc/14-619_opn.pdf#xml=http://www.ca2.uscourts.gov/decisions/isysquery/73af4a5d-25eb-468d-ad34-9bb571816aed/5/hilite/