Maryland Code, Land Use § 3-304

(a) Subject to subsection (b) of this section, a local jurisdiction shall include in its comprehensive plan any plan element required under Subtitle 1 of this title in accordance with the review schedule for the local jurisdiction under § 3-303 of this subtitle.

(b) On request of a local jurisdiction and for good cause, the Department of Planning may extend the deadline under subsection (a) of this section for that local jurisdiction by no more than two 6-month extensions.

(c) A local jurisdiction that is not in compliance with this section after the deadline under subsection (a) of this section or after the expiration of any extension granted under subsection (b) of this section, may not change the zoning classification of a property until that local jurisdiction has complied with this section.