The Delhi Municipal Corporation Act, 1957
471. Limitation of time for prosecution.-
No person shall be liable to punishment for any offence against this Act or any rule, regulation or by-law made thereunder, unless complaint of such offence is made before a municipal magistrate within six months next after-
(a) the date of the commission of such offence, or
(b) the date on which the commission or existence of such offence was first brought to the notice of the complainant.