Unless a person who has received disability severance pay again becomes a member of an armed force, the National Oceanic and Atmospheric Administration, or the Public Health Service, he is not entitled to any payment from the armed force from which he was separated for, or arising out of, his service before separation, under any law administered by one of those services or for it by another of those services. However, this section does not prohibit the payment of money to a person who has received disability severance pay, if the money was due him on the date of his separation or if a claim by him is allowed under any law.