We see these childish spats in OOC all the time and frankly its pathetic, if you hold an OP and it is indeed ninja'd, then I am afraid to say that it is all part and parcel of the game. If you want to keep your OP's defend them or lose them, lets face it these are war zones!
If you believe a war zones goes to sleep because you are tired or need a bite to eat, snuggle up to your girlfriend on the sofa and watch Titanic maybe, then you are living in a fantasy world go play WoW. If you lose an OP because you have not been there to defend it, get over it and retake it.
If you feel you are being cheated out of an OP as ninja hacking is unfair, exercise your right to complain through a GM, good luck with that, or you could eliminate your anguish and not take OP's you cant defend and maybe be carebears in Plaza 1