MOP, Bk 3, v.4, 150
“6. Third lieutenants shall be promoted to the grade of second lieutenant upon having served two years in their grade, and second lieutenants shall be promoted to the grade of first lieutenant upon completion of three years of service in their grade:Provided, that, any officer appointed to the Army, with position on the seniority list above the junior officer of the Army, shall be considered to have, for purposes of effecting promotions under the provisions of this paragraph, as much commissioned service as that of any officer below him on the list.”Done at the City of Manila, this 1st day of March, in the year of Our Lord, nineteen hundred and forty, and of the Commonwealth of the Philippines, the fifth.