(a) The board consists of:
(1) one director elected from each commissioners precinct; and
(2) three directors elected from the district at large.
(b) Unless four-year terms are established under Section 285.081, Health and Safety Code:
(1) directors serve staggered two-year terms; and
(2) an election shall be held annually on the May uniform election date, or another date authorized by law, to elect the appropriate number of directors.