function release(address _addr) external {
        require(owners[msg.sender] || msg.sender == _addr);
        require(block.timestamp >= releaseTimestamps[_addr]);
        uint256 amount = lockAmounts[_addr];
        lockAmounts[_addr] = 0;
        releaseTimestamps[_addr] = 0;
        token.transfer(_addr, amount);
    }