(a) If a vacancy occurs in the office of director, the remaining directors by majority vote shall appoint a director for the unexpired term.
(b) The appointed director must have the qualifications required by Section 1118.052.
(c) If the number of directors is reduced to fewer than three for any reason, the remaining directors shall immediately call a special election to fill the vacancies. If the remaining directors do not call the election, a district court, on application of a district voter or taxpayer, may order the directors to hold the election.