(6)Where any such amendment has the effect of enhancing the assessment or reducing a refund already made, the [Assessing Officer] [Substituted by Act 4 of 1988, Section 2, for " Income-tax Officer" (w.e.f. 1.4.1988).] shall serve on the assessee a notice of demand in the prescribed form specifying the sum payable, and such notice of demand shall be deemed to be issued under section 156 and the provisions of this Act shall apply accordingly.
