Section 3(3) in The Gujarat Provision for Disqualification of Members of Local Authorities for Defection Act, 1986
(3)An appointed councillor or, as the case may be, member shall be disqualified for being a councillor or, as the case may be, a member if he joins any political party after the expiry of six months from the date on which he is appointed as such councillor, or as the case may be, a member.
