AUSTIN, Texas--(BUSINESS WIRE)--Fitch Ratings assigns an 'AA-' rating to Edinburg, Texas' (the city) bonds as follows: --Approximately $7.5 million utility system revenue refunding bonds, series 2015. The bonds are scheduled to sell as early as June 24, depending on market conditions. Proceeds from the bonds will be used to refund a portion of the series 2006 outstanding obligations for debt service savings and to pay issuance costs. In addition, Fitch affirms the following ratings (pre-refundi