Whenever a landowner who desires to challenge, on substantive grounds, the validity of this chapter or map or any provision thereof, which prohibits or restricts the use or development of land in which he/she has an interest submits to the Board of Commissioners a curative amendment with a written request that his challenge and proposed amendment be heard and decided, it shall be the duty of the Board of Commissioners to hold a public hearing thereon within 60 days of said request, notice of said hearing to be given as provided in § 295-3001.