(a) An oil, gas, and mineral lease executed by a personal representative may be amended by an instrument that provides that a shut-in gas well on the land covered by the lease or on land pooled with all or part of the land covered by the lease continues the lease in effect after the lease's five-year primary term.
(b) The personal representative, with the approval of the court, shall execute the instrument according to the terms and conditions prescribed by the instrument.