GST notification amendment substitutes the listed goods to include fly ash bricks, aggregates and blocks, effective retrospectively. The Government amends Notification No. S.O. 183 of 19 April 2022 by substituting, in the TABLE against serial number 4, the entry in column (3) with 'Fly ash bricks; Fly ash aggregates; Fly ash blocks', with the substitution deemed to have come into force w.e.f. 18th July, 2022.