We had some luck when we got the info regarding rules from the district directly and left a message for the principal about what we had been told by the district. In our instance, the local districts had K cut offs of 5 by sometime in June (one district) and 5 by 9/15 (the other two districts). One of the 9/15 districts changed the cut off to 10/1 the year dd10 was going to be 5 in the last couple days of Sept.
The principal of our neighborhood school wouldn't admit that the cut-off had been changed and wouldn't give me any certain answer on enrolling dd. We kept being told that they were looking into in but as far as they knew the cut off was still 9/15. I called the district and left a msg for the principal as to who I had spoken with at the district and what they said and that I'd be there for K registration b/c dd was age eligible. The principal suddenly got notification from the district that the cut off had changed after that and I had no problems with getting dd enrolled.