I can't point out where is wrong.
but I can tell you fact that the current block is 88258,the block reward is still 256
And this is completely right according to what I have said.
First halving had place at block 43,200 from 512 to 256
and second halving will take place at block 129,600 from 256 to 128.
So we must have the reward of 256 DCN now.
Edit: fixed one my mistake.