Application of income-tax law: central Act commencement affirmed while prior local tax law is preserved for the specified prior year. The Income-tax Act, 1961 is to come into force in Sikkim from the previous year relevant to the assessment year commencing 1 April 1990, notwithstanding earlier notifications. Any Sikkim law corresponding to the Income-tax Act that was in force immediately before that commencement is deemed never to have ceased for the previous year 1 April 1988 to 31 March 1989 and continues to apply for levy, assessment, collection of income-tax, penalties and related purposes.