The provisions regarding the maximum height of mixed use buildings within 25 feet of a street line, as set forth in Section 123-661 (Mixed use buildings in Special Mixed Use

Districts with R3, R4 or R5 District designations), shall be modified in the Dutch Kills Subdistrict, where the designated Residence District is an R5 District, as follows:

(a)        in designated R5B Districts, no building or other structure shall exceed a height of 33 feet within 25 feet of a street line;

(b)        in designated R5D Districts, no building or other structure shall exceed a height of 45 feet within 25 feet of a street line.