La. Stat. tit. 33 § 2410
The director shall, subject to the rules, establish and maintain promotion lists and employment lists for the various classes of positions in the classified service which are necessary or desirable to meet the needs of the service. On each promotion list and employment list, the eligibles shall be ranked in the order of their ratings earned in the test given for the purpose of establishing the list, subject, however, to subsequent revision by the director in accordance with R.S. 33:2418.
The director shall, subject to the rules, determine at the time any promotion list or employment list is established, the period during which the list shall remain in force, which shall be not less than six months nor more than three years. The director may extend the period by order made before the expiration of the list, but no list shall be extended to a time more than three years from the original establishment thereof, and a statement of the reasons for any extension shall be entered in the records of the department. The director may consolidate or cancel promotion lists and employment lists as the needs of the service require and as authorized by the rules. Unless otherwise provided in the rules a promotion list or employment list which has been in force for six months or more shall be deemed cancelled upon the establishment of a new promotion list or employment list, for the same class of positions.
La. R.S. § 33:2410