A proposed subdivision of land is subject to these regulations, where such division is along an existing street, does not involve the opening, widening or extension of any street or road, and which involves no more than five lots (four lots and the original parcel remaining) after the original tract has been completely subdivided. Such a subdivision may be submitted to the Commission for approval without the requirement of a record plat. If the Commission is satisfied that such proposed subdivision of land is not contrary to applicable platting, subdivision or zoning regulations, it shall, within thirty working days after submission, approve such proposed subdivision.