I don't have a definitive answer but during the ACG Panel on Sunday, At the 2:40:53 time reference Mike mentions that it got laid out for it to be able to be released. Linda mentions that last year's Open got laid out last year but never got released. Keith said he's hopeful that the Opens will make it out into the wild more than they have in the past.
Based on my experience at Gen Con it did seem like it was released in error (i.e. too early) so I'm not sure exactly when it was planned to be released and ready to run locally.