If the position of mayor should become vacant, the board of aldermen shall, within twenty days, appoint a person to fill the vacancy who meets the qualification of office. See R.S. 18:602(A). If the board fails to appoint a replacement within twenty days, then the Governor is authorized to appoint an individual to fill the vacant position. See R.S. 18:602(D). If less than 18 months remain in the present term at the time the vacancy occurs, then the appointed individual shall serve out the remainder of the present term. If the vacancy occurs with more than 18 months remaining in the present term, then under R.S. 18:602(E)(2)(a), the board of aldermen shall within twenty days after the vacancy occurs, issue a proclamation ordering a special election to fill the vacancy. If the board fails to make the proclamation, then the Governor shall issue the proclamation ordering the special election be held. The appointed individual shall serve until the newly elected mayor is installed following the special election.