BTW, we never had any image for rpi2/rpi3 that was using the
kernel-generic repo
Ok, the values are set in /etc/yum/vars.
[root@dc03 vars]# ll total 12 -rw-r--r--. 1 root root 6 Dec 5 2016 infra -rw-r--r--. 1 root root 8 Oct 31 10:00 kvariant -rw-r--r--. 1 root root 2 Sep 1 07:02 releasever