USCIS announced that it will accept labor certification substitution requests in the context of Form I-140, Immigrant Petition for Alien Worker, filings it receives on Monday, July 16, 2007.  USCIS previously announced that it would reject all labor certification substitution requests filed on or after July 16, 2007.  The new DOL regulation that prohibits substitutions of an alien beneficiary on any application for permanent labor certification will go in effect July 17, 2007 and not July 16, 2007.