Fla. Stat. § 373.566

The governing board shall have authority to issue refunding bonds to take up any outstanding bonds of said district falling due and becoming payable, when, in the judgment of said board, it shall be for the best interests of said district so to do. The said board is hereby authorized and empowered to issue refunding bonds to take up and refund all bonds of said district outstanding that are subject to call and termination, and all bonds of said district that are not subject to call or redemption, where the surrender of said bonds can be procured from the holder thereof at prices satisfactory to the board. Such refunding bonds may be issued at any time when in the judgment of said board it will be to the interest of the district financially or economically by securing a lower rate of interest on said bonds or by extending the time of maturity of said bonds, or for any other reason in the judgment of said board advantageous to said district.