Each establishment along a designated street frontage shall be located within 10 feet of the lot line on which it is required to front for the full length of the frontage of that establishment, except that, where a street wall recess at curb level permitted under Section 81-43 (Street Wall Continuity Along Designated Streets) extends a greater distance from the lot line, the length of frontage of any establishment adjoining that recess may be located at an equal, but not greater, distance from the lot line.