Section 4(1A)(c) in The Gujarat Motor Vehicles Tax Act, 1958
(c)where such vehicle is to be used or kept for use in the State for a period equal to a month or more than a month the tax shall be leviable at the rate specified in clause (i), (ii) or (iii) of sub-section (1) of section 4, according as such period is equal to the period specified in the said clause (i), (ii), or (iii) as the case may be, irrespective of whether such period expires at the end of a quarter or not;