Looks like I made a bone-head mistake! While uprading from F11 to F12, I got a message saying I needed to clear some space in /boot and suggested I remove old kernals - I did, but got a message saying still needed more space. I made (I now realize) the mistake of removing /boot/upgrade/install.img.
The upgrade continued, however upon reboot I'm getting a message that /upgrade/install.img is not being found. Is this something I can replace?