Exemption limit increase and extension of higher notional credit scheme; central excise notification amended to take effect in April. The notification amends Notification No. 175/86 to raise the full exemption limit, extend the higher notional credit scheme for an additional year, and insert 'tyre flaps of rubber' into the Annexure list of exempted items; the amendments are effected under the Central Excises and Salt Act, 1944 and commence on the specified date in April 1990.