Lyndon Johnson actually said...
Any person who left a competitive position to enter the armed forces of the United States who would meet the requirements of section 1 except for absence in the armed forces on the date of this order and who is re-employed in a competitive position in the Postal Field Service within 120 days after discharge from the armed forces under honorable conditions may have his appointment converted if he is recommended by his appointing officer within ninety days after his re-employment and qualifies in such examination as the Civil Service Commission may prescribe.
10/23/1964