Standard&Poor's Ratings Services changed its rating to 'AA+/A-1+' from 'A/A-1' on Washington State Housing Finance Commission's variable-rate demand multifamily housing revenue bonds (Discovery Heights Apartments Project), series 2010, issued on behalf of Block 24 LLC, based on the replacement of the existing letter of credit from Bank of America (A/A-1) with a direct-pay credit enhancement agreement provided by Freddie Mac (AA+/A-1+). The Freddie Mac credit enhancement agreement will provide credit coverage of principal and interest due on the bonds plus coverage of the purchase price in the event of a failed remarketing. The credit facility is sized at principal plus 35 days interest in the variable mode and 189 days interest in the reset and fixed-rate modes. The