Deeming provision for excise validates a prior notification on matches and limits refund proceedings accordingly. Provision validates and backdates a notification exempting certain matches from excise duty by deeming that notification to have always been in force and to prevail over other notifications for the prior period, thereby rendering actions, assessments and collections during that period valid; it bars refund proceedings for duties validly collected, requires refunds where duties should not have been collected under the deeming, permits recovery where duties were not collected or improperly refunded, and includes a non-punishment clarification.