Raising fresh claim via rectification under section 154 post facto judicial decision

Facts:

Assessee individual moved a belated rectification petition before AO claiming exemption on gratuity income under section 10(10AA) for first time which was rejected by AO and CIT(A). Plea raised was consequential to a judicial verdict the rectification was legitimate to be considered on merits. This went in appeal to ITAT by assessee -

Held against the assessee that they had raised a fresh claim via a belated rectification which is not the purpose or intent of section 154 as there was no mistake apparent on record. Assessee ought to have come via an appeal petition. 

Case: Jaipal Singh Dendsay v. ITO 2024 TaxPub(DT) 36 (Del-Trib)