Section 3(3)(i) in The Indian Forest Service (Regulation of Seniority) Rules, 1997
(i)the year of allotment of a direct recruit officer shall be the year following the year in which the competitive examination was held: Provided that if a direct recruit officer is permitted to join probationary training under Sub-rule (1) of Rule 6 of the Indian Forest Service (Probation) Rules, 1968 with the direct recruit officers of subsequent year of allotment, then he shall be assigned that subsequent year as the year of allotment.