Section 2(1)(b) in Central Duties of Exercise (Retrospective Exemption) Act, 1986
(b)maintaining the effective rates of duties of excise in respect of certain goods at the level obtaining prior to the 1st day of March, 1986 notwithstanding the changes in the rates of duties of excise made by the Finance Bill, 1986, shall, in so far as such notification relates to such goods, be deemed to have, and to have always had, effect on and from the 1st day of March, 1986.