Retrospective amendment of customs notification enables refunds for duties collected, subject to a statutory six month claim period. The Government notification G.S.R. 153(E) dated 1 March 2011 is deemed retrospectively amended as specified in the Second Schedule, with the Central Government deemed to have had retrospective amendment power. Refunds must be made of customs duty collected but not collectible had the amended notification been in force, and refund claims must be filed within six months from the Finance Bill, 2013 receiving Presidential assent; section 27 of the Customs Act, 1962 applies to such refunds.