Date substitution in tax exemption provision shortens eligibility window and changes commencement and applicability of relief in income tax provision. The Finance Act, 2007, effective 1 April 2008, amends sub-section (2) of the relevant income-tax provision by substituting '1st day of April, 2012' with '1st day of April, 2007' in clause (a)(i) and clause (b)(i), thereby modifying the temporal cut-off referenced in those sub-clauses while leaving their substantive terms intact.