All traffic-control devices heretofore installed by authority of the Board of Commissioners and which are in place on the effective date of this code shall continue to be official until the time as they may be removed by authority of the Board of Commissioners; and until they are so removed it shall be unlawful for any person to fail to comply with any instruction or directive indicated by any official traffic-control device.
(Prior Code, § 11-16) Penalty, see § 10.99