PUBLIC LAWS-CHS. 402, 403-AUG. 5, 8, 1949 Adjustment oflineal position. 61 Stat. 833 . 34 U.S. C., Supp. II, § 211a. Ante, p. 567 . Temporary promo- tion below captain. Selection boards. Ante, p. 569. Supra. 61 Stat. 829. 34 U.S.C., Supp.II, i 3c note. 61 Stat. 869. 34U.S . C ., Supp. I, 211b. Promotion zone. Ante, p. 569; tupra. 61 Stat. 833. 34U. S. C., Supp.II, 211a. Ante, p. 567. with the maximum period of three calendar years of active service without regard to the actual time elapsed between matriculation and qualification for the professional or graduate degree held. SEC. 4 . The lineal position of each officer described in section 2 of this Act shall be adjusted by advancing such officer on the lineal list established pursuant to section 304 of the Officer Personnel Act of 1947, as amended, in accordance with his active service credit deter- mined pursuant to sections 2 and 3 of this Act. If such adjustment would advance any such officer to a grade higher than the grade in which he is serving under a permanent or temporary appointment on the effective date of this Act, he shall be assigned a position on the lineal list senior to the line officer in his grade not restricted in the performance of duty who was the junior officer in the promotion zone last established for his grade and, when selected for promotion to the next higher grade, shall upon promotion be advanced to the position on the lineal list commensurate with his active-service credit: Pro- vided further, That officers described in section 2 of this Act below the grade of captain whose names appear on a promotion list on the effective date of this Act, if not then eligible for temporary promotion to the next higher grade under other provisions of law, shall become so eligible on that date. SEC. 5 . As soon as practicable after each officer described in section 2 of this Act has been advanced on the lineal list pursuant to section 4 of this Act, the Secretary of the Navy shall appoint and convene selection boards pursuant to the provisions of title III of the Officer Personnel Act of 1947, as amended, to consider for temporary promo- tion to the next higher grade all eligible officers designated for special duty pursuant to section 401 of that Act. The promotion zone for each grade shall consist of those officers who have been advanced pur- suant to section 4 of this Act, to a lineal position in such grade senior to the line officer of that grade not restricted in the performance of duty who was the junior officer in the promotion zone last established for that grade. Notwithstanding any other provision of law, all officers recommended for temporary promotion in the approved report of a selection board, appointed and convened as herein provided, shall be eligible for temporary promotion to the next higher grade on the date of approval of such report. Upon promotion to a higher grade and advancement on the lineal list pursuant to section 4 of this Act, each such officer shall be deemed to have as much service in grade as the lile officer not restricted in the performance of duty who has not lost numbers or precedence and who is next junior to such officer on the lineal list. SEC. 6. The Secretary of the Navy shall prescribe all necessary and proper regulations, not inconsistent with the provisions of sections 2, 3, 4, and 5 of this Act, for the computation and crediting of the active service credit provided by this Act to the officers entitled thereto, and for their appropriate advancement on the lineal list of officers estab- lished pursuant to section 304 of the Officer Personnel Act of 1947, as amended. Approved August 5, 1949. [CHAPTER 4031 August 8, 1949 [S. 11841 [Public Law 211] National Housing Act, amendments. AN ACT To encourage construction of rental housing on or in areas adjacent to Army, Navy, Marine Corps, and Air Force installations, and for other purposes. Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That the National 570 [63 STAT.