Section 171(4) in The West Bengal Panchayat Act, 1973
(4)An elected member of a Sthayee Samiti shall hold office for a period of [five years] [Words substituted for the words 'four years' by W.B. Act 12 of 1982, w.e.f. 4.8.1982.] or for so long as he continues to be a member of the Zilla Parishad, whichever is earlier.