Section 89 relief clarifies eligible salary-related receipts and allows CBDT discretion for other payments under Rule 21A provisions. Section 89 relief applies to salary or family pension received in arrears or in advance; gratuity in excess of exemption; compensation on termination of employment; and commuted pension in excess of exemption. The listed categories are recognised for computation under the statutory relief mechanism set out in the rules. For payments other than those specified, the administrative authority may consider relief after examining each case under the regulatory framework.