A temporary restraining order preventing a major overhaul of the city’s hiring and promotional processes for thousands of civil service employees was extended Thursday until Oct. 17, when representatives of the city’s police and fire unions and the Landrieu administration will argue about whether the changes should be blocked permanently.

The order was set to expire Friday, when the hearing was originally scheduled. Civil District Court Judge Ethel Simms Julien reset it for next month after the Civil Service Commission retained new counsel to represent it, according to the order.

The proposed changes, pushed by Mayor Mitch Landrieu’s administration, would affect classified employees, meaning those workers who have civil service job protection and are not at-will political appointees.

The proposed revisions to more than 30 civil service rules would give City Hall supervisors greater flexibility in hiring, evaluating, promoting and rewarding employees.

One major source of division is the proposed elimination of the “rule of three,” which allows department heads and hiring managers to consider only the top three eligible candidates for a promotion or an open position, based on how they score on an aptitude test.

The changes are designed to ensure that the city can hire the best applicants for available positions and retain high-performing employees, Landrieu administration officials argue.

Critics counter that the changes would leave the city’s hiring and promotional process open to discriminatory practices and favoritism. They made their case Aug. 25 before the Civil Service Commission, which then voted 3-1 to approve the changes, with one commissioner abstaining.

The local chapter of the Fraternal Order of Police filed suit after the vote, challenging the commission’s action. The suit requested the temporary restraining order and temporary and permanent injunctions.

Follow Danny Monteverde on Twitter, @DCMonteverde.