When the state legislature says they had no say in the decision is that because 1)the election commission took it upon themselves to bestow this power to themselves? or 2) did the state legislature defer this power to the election commission at some earlier point in history?
I would be surprised if they expressly gave them this degree of flexibility. There is also the constitutional decre that the election is to be held on a single day. Of course, that has been abused by some states aleady, but there is a big difference between early voting, where voters are essentially permitted to tee up their votes in advance, and late voting which fairly well erases that constitutional dictate.
*decree