(a) No person shall be eligible as a candidate for member of Council District Numbers 1, 2, 3, 4, 5 or 6, unless he is at the time a bona fide resident of District 1, 2, 3, 4, 5 or 6, and has resided therein for a period of at least twelve (12) months immediately preceding election day. Any Council candidate residing in an area annexed to the city for less than twelve (12) months is eligible if the candidate resided in the area continuously for twelve (12) months immediately preceding election day, including time prior to annexation, and the area of residency is included in the District where the candidate seeks election as prescribed by the Texas Election Code as amended. He shall continuously reside in said district during his term of office. The candidate for Mayor may be a resident of any portion of the city, shall have resided in the city for a period of twelve (12) months immediately preceding election day, and shall continuously reside within the city during his term of office. Any Mayoral candidate residing in an area annexed to the city for less than twelve (12) months is eligible if the candidate resided in the area continuously for twelve (12) months immediately preceding election day, including time prior to the annexation, as prescribed by the Texas Election Code, as amended.
(b) If the district in which a person will have resided for at least twelve (12) months immediately preceding election day will change because of a district boundary, the person is eligible to become a candidate:
(1) for the new district assigned to his residence; or
(2) for the previous district of his residence if he moves his residence within the revised boundaries of that district prior to becoming a candidate for election.