If the local government approves the request for a joint hearing with respect to a State unit, that State unit has 10 days after receipt of the notice from the Coordinator to: decide whether to participate in a joint hearing; and give notice of its decision to: the applicant; the local government; and the Coordinator. The Coordinator shall give any other State unit involved in the hearing notice of a decision made by a State unit under subsection (a) of this section. If there is only 1 State unit affected and the local government elects to have a joint hearing, the State unit shall participate in the joint hearing, unless it is entitled to an extension as provided in § 11-521 of this subtitle.