In all districts, after December 15, 1961, any zoning lot or other tract of land, as applicable, and anything therein or thereupon, including any development, enlargement, extension, change of use, new or existing use, conversion, alteration, site alteration, relocation, reconstruction and any building or other structure shall be subject to the regulations of this Resolution; and shall continue to be subject to the provisions of this Resolution in effect at the time of such development, enlargement, establishment of  or change of use, conversion, alteration, site alteration, relocation or reconstruction, unless such provisions are modified by an amendment of this Resolution applicable to buildings or other structures or uses existing at the time of such amendment.

Where an existing use or building or other structure is non-conforming or non-complying, the provisions of Article V (Non-Conforming Uses and Non-Complying Buildings) may apply.