Yeah, they really need to fix that. They say it is supported, but none of our A3\A5 users and computers could enroll into the program when we tried it out. Only the E3\E5 users worked properly... We rolled back to normal policies just to not have to manage two different methods to publish updates at the same time, because of the administrative headache that often comes with that.
And based on their documentation, A3\A5 users don't share feature parity with E3\E5 in Autopatch either, so I don't know if we would have used it either way, as we would have to micromanage all the non-supported features separately, but ONLY for A3\A5-users... I don't know why Microsoft feels the need to limit the features for Autopatch on A3\A5-licenses, as Enterprise and Education-versions of Windows have always shared 99.9% feature parity.
And A3\A5 is where this feature would have shined in my opinion, as educators really don't want any downtime in their classrooms, believe me...