Subject to subsection (b) of this section, on written request of an entity subject to this title, the appropriate advisory body shall issue an advisory opinion regarding the application of this title. On written request of any other entity, the appropriate advisory body may issue an advisory opinion. The appropriate advisory body may issue informal advice instead of an advisory opinion. Except as provided in §§ 5–501.1 and 5–502(f) of this title, information related to informal advice provided under this subsection shall remain confidential and is not subject to the requirements of § 5–303 of this subtitle.