But if I understood correctly most of the money is held by havelock (can somebody confirm that?).
Also twentyseventy has an interest to let the derivative run as long as possible, because he gets a comission of 1%.
That's correct, Havelock current manually confirms all withdrawals from fund accounts. Since there shouldn't be any reason to withdraw coins from BDD, the likelihood of this being approved is fairly low.
And if I remember correctly, that 1% is actually 0.4% (Havelock fees) and 0.6% (his commission).
The 1% NAV/U premium that buyers of EXCH pay is not going to twentyseventys pocket. It is added to the funds NAV, very slightly increasing the value of B.SELL whenever EXCH is bought.
Twentyseventy apparently worked out a deal with Havelock for his income. We don't know what it is, but I suspect something like getting a part of all trade fees earned by Havelock on BDD-trades.