(a) It is a ground for removal from the board if a member:
(1) does not have at the time of appointment or election the qualifications required by Section 2054.052;
(2) does not maintain during service on the board the qualifications required by Section 2054.052;
(3) cannot because of illness or disability discharge the member's duties for a substantial part of the term for which the member is appointed or elected; or
(4) is absent from more than half of the regularly scheduled board meetings that the member is eligible to attend during a calendar year.
(b) The validity of a board action is not affected by the fact that it is taken when a ground for removal of a board member exists.