Comment 3 for bug 1007543

If you need to specify a specific answer use the following

sudo sh -c 'echo "y\n\ny\nN\nN\nN\nN\nN\nN\nN\nN\nN\nN\nN\n" | DEBIAN_FRONTEND=noninteractive /usr/bin/do-release-upgrade'

I agree though, the documentation should be a little better the functionality is there.