After any district change is adopted to the Official Zoning Map, the Planning and Zoning Administrator shall cause the Official Zoning Map to be updated by the preparation of a new map. The new Official Zoning Map shall note the effective date of the change and shall designate the exact location of the change. The map shall be signed by the Planning and Zoning Administrator and attested by the City Council Clerk. The previous zoning map shall be permanently filed and remain in the custody of the Planning and Zoning Administrator.