Section 124(8) in The Naval Ceremonial, Conditions Of Service And Miscellaneous Regulations, 1964
(8)Rank on Entry. - (a) Those possessing a Certificate of Competency referred to in cl. (a) of sub-regulation (3) shall be entered as a Lieutenant. Suitably qualified candidates may be granted up to a maximum of 2 years seniority in the rank at the discretion of the Chief of the Naval Staff.(b)Others shall be entered as an acting Sub-Lieutenant.