Continuation of recovery proceedings allowed after appeal alters tax demand; fresh demand notice not required for prior or reduced amounts. When a demand notice has been served and an appeal, revision or other proceeding is pending, recovery may continue after disposal: if dues are enhanced the Commissioner issues a notice only for the increased amount and proceedings continue without a fresh notice for existing demand; if dues are reduced no fresh notice is required, the Commissioner must intimate the reduction to the person and the recovery authority, and proceedings continue in respect of the reduced amount from their prior stage.