Section 2(g) in The Indian Cost Accounts Service Rules, 2015
(g)"Regular service" in relation to any grade means the period or periods of service in that grade, rendered after selection, under these rules, to that grade, and includes any period or period,-(i)taken into account for purposes of seniority in the case of those appointed at the initial constitution of the service;(ii)during which an officer would have held a duty post in that grade but for his being on leave or otherwise not being available for holding such post;
