Nothing contained in R.S. 47:338.92 through 338.96 shall be construed to affect the purposes for which the proceeds of any sales tax authorized or levied prior to January 1, 1967 shall be used, and in all such cases the disposition of the proceeds of sales taxes heretofore authorized or levied within the district shall be made in accordance with the authorization under which such tax was levied and is being collected.
La. Revenue and Taxation § 47:338.96