(a) Notwithstanding other provisions of this subchapter, the department will renew a permit for a nonconforming sign only if the sign structure was lawfully erected and has been maintained in accordance with the permit being renewed.     
      (b) A sign that was legally erected before March 3, 1986 in a railroad, utility, or road right of way that is not owned by the state or a political subdivision may be maintained as a nonconforming sign if all other requirements of this subchapter are met.     
      (c) A nonconforming sign may not be:      
        (1) removed and re-erected for any reason, other than a request by a condemning authority; or       
        (2) substantially changed, as described by §21.191 of this subchapter (relating to Repair and Maintenance of Commercial Signs).       
     Source Note:        The provisions of this §21.150 adopted to be effective July 1, 2011, 36 TexReg 2418; amended to be effective March 14, 2018, 43 TexReg 1446