I have a grub config that defaults to booting another partition. Everytime the kernel is updated the grub updater changes that back to the first kernel. When the default in grub is set to a non fedora kernel it should never change that.
Just edit /etc/sysconfig/kernel and set UPDATEDEFAULT=no Doing that automatically is probably too difficult to get right for everyone.
if (default points to vmlinuz-$(uname -r)) update else do not update not difficult at all.