You did not mention whether you wanted lunch or dinner?
This is what happened to us back at the end of April: kept calling for ADR for either breakfast or dinner, finally got an ADR for breakfast at 8am on Tues of our trip. Well Sun, we go to have breakfast at the Concourse Steakhouse around 7:15. We were staying at the CR. So DH says stay here, I am going to check something, he runs over to Chef Mickey, with another dad who decided to do the same thing and both families got in. LUCKILY I had the camera and autograph books with me bc we had not planned to do this. So later that week we cancelled our CM ADR so I hope some other family got to use it instead.
We did get in two other places on our trip w/o ADRs SciFi lunch, and Concourse for dinner both of which we could not get beforehand.