If a member ceases to hold office for any reason whatsoever, he is immediately replaced by a substitute. If there is no substitute, a supplementary election is held to fill the vacant seat as from the date on which the vacancy is established. In this case, the term of office of the member thus elected shall be that remaining until the date on which the term of office of the member he replaces would have expired.
The member thus elected shall be of the same gender as the member he replaces.