All reciprocity registration or driver agreements, arrangements and declarations relating to vehicles or drivers in force and effect on May 5, 1964, shall continue in force and effect until specifically amended or revoked as provided by law or by such agreements or arrangements.

21 Del. C. 1953, § 410; 54 Del. Laws, c. 274; 60 Del. Laws, c. 451, §§ 5, 6