Notwithstanding any other provision of law, including specifically any temporary provisions in the general appropriations act for fiscal year 2008-2009, coastal counties and municipalities may adopt by reference or otherwise the provisions in the 2006 International Residential Code (IRC) necessary to prevent properties insured by the National Flood Insurance Program (NFIP) being retrograded to a lower class for purposes of the flood insurance premium discounts allowed jurisdictions participating in the NFIP's community rating system.