Is it true that people in the Sea Org sign a billion-year contract?

IS IT TRUE THAT PEOPLE IN THE SEA ORG SIGN A BILLION-YEAR CONTRACT?

The first Sea Organization members formulated a one-billion-year pledge to symbolize their eternal commitment to the religion and it is still signed by all members today. It is a symbolic document which, similar to vows of dedication in other faiths and orders, serves to signify an individual’s eternal commitment to the goals, purposes and principles of the Scientology religion.