Miss. Code § 49-25-15
Any junkyard lawfully in existence on June 16, 1966, which does not conform to the exceptions contained in Section 49-25-7, or that cannot be made to so conform by screening as provided in this chapter, shall be required to be removed under Section 49-25-13 by July 1, 1970, or as soon thereafter as funds are available for that purpose. Any junkyard located along any highway made a part of the interstate or primary system after June 16, 1966, shall be considered to have been lawfully established for the purposes of this chapter; and in the event any such junkyard does not conform to the exceptions in Section 49-25-7, or cannot be made to so conform by screening as provided in this chapter, it shall be required to be removed under Section 49-25-13 by the end of the fourth year after it shall be determined that it is nonconforming or as soon thereafter as funds are available for that purpose.
Miss. Code § 49-25-15