Section 12(2)(b) in The Orissa Finance Service Rules, 1979
(b)The selection of persons for inclusion in the lists for promotion under Sub-rules (2), (3) and (4) of Rule 3 shall be based on merit and suitability with due regard to seniority. The names of the officers included in every such list shall be arranged in the order of their seniority in the cadre from which they are selected for promotion :