For any zoning lot located between Fifth Avenue, Duke Ellington Circle, East 109th Street and East 110th Streets:

(a)        commercial uses shall only be permitted beyond 100 feet of Fifth Avenue and shall be restricted to office uses listed in Use Group 6B;

(b)        the underlying district sign regulations shall not apply. In lieu thereof, signs accessory to a commercial use shall conform with all the sign regulations applicable in C1 Districts, except that illuminated signs shall not be permitted and, within 100 feet of Fifth Avenue, signs shall conform with the sign regulations for Residence Districts set forth in Section 22-30.