Please read carefully the blog "OPEN Platform": https://blog.openfuture.io/announcements/open-bounty-audit-completed-and-final-results/
There it says it all.
Quote: "Given every one of our token holders are vested, the fact that our bounty program was one of the largest programs, and represents a significant amount of tokens, a vesting of everyone with a total USD value of tokens at or above $50 for a total of 8 weeks is required to be fair to all token holders. We are doing this to be equitable to all of our other early stakeholders who have been vested for even longer terms and have also put in a considerable amount of work in supporting the project. Those having a total token value of below $50 will receive their tokens immediately. For those with over $50 in total token value, the first distribution will take place now, the second distribution in 4 weeks from today, and the third distribution in an additional 4 weeks".