(a) A presiding judge must be at the time of appointment:
(1) a regularly elected or retired district judge;
(2) a serving or retired business court judge;
(3) a former judge with at least 12 years of service as a district judge or business court judge; or
(4) a retired appellate judge with judicial experience on a district court.
(b) If the judge is retired, he must have voluntarily retired from office, must reside within the administrative region, and must have certified his willingness to serve.