hi there
on the thought that the twins are excited about moving into "big girl beds" perhaps you could say to them that big girls dont have dummys so if they want to sleep in big girl beds then they have to be big girls and throw the dummy away,

at one i gave my son the choice he could throw away his dummy or throw away his bottle he chose to throw away the bottle so i made him put it in the rubbish himself, at two i gave him the choice of dummy or bear he chose the dummy but i gave in to the tantrums then when he was two and a half he left dummy and bear at my mums house by accident, he got the bear back but the dummy fairy took the dummy and he never asked for it again,

each child is individual but maybe the big girl bribe might be worth a try