La. Stat. tit. 39 § 994
If more than one series of bonds is issued hereunder, payable from the revenues of any project or facility acquired, constructed or improved from the proceeds of bonds issued under the provisions of this Part, priority of lien on such revenues shall depend on the time of the delivery of the bonds, each series enjoying a lien prior and superior to that enjoyed by any series of bonds subsequently delivered, except that where provision is made in the proceedings authorizing any issue or series of bonds for the issuance of additional bonds in the future on a parity therewith, pursuant to procedure or restrictions provided in such proceedings, additional bonds may be issued in the future on a parity with such issue or series in the manner so provided in such proceedings.
La. R.S. § 39:994