Transitional input tax credit: prescribed time and manner for claiming unavailed credits, applied retrospectively to the commencement period. The amendment inserts a requirement in multiple sub sections of section 140 that transitional input tax credit and claims in respect of goods held in stock on the appointed day be made 'within such time and in such manner as may be prescribed,' thereby subjecting entitlement to prescribed procedural time limits and modes of claiming while retaining existing substantive eligibility, with retrospective effect to the commencement of the regime.