Salaried income threshold revised, altering filing exemption and providing interest adjustment with notice and refund procedures. Amendment to Section 139 revises the salary-based filing exemption by redefining clause (b) to base exemption on salary income excluding non-monetary benefits and omits the prior Explanation; it replaces Explanation 2 in sub-section (8) to treat first assessments under section 147 as regular assessments and substitutes clause (b) to require corresponding increase or reduction of interest after specified assessment/appellate orders, mandating a notice of demand when interest is increased and refunding excess interest when reduced.