During the upgrade, it lost networking. There are several posts on the web but, essentially, the "/run/network" directory didn't exist anymore. Once I found that, I manually created the directory, ifup, and all was good. If you reboot, the directory disappears again and has to be recreated. There appeared to be two reported ways to get the directory to stay:
1. Create the directory as root (not a regular account using sudo)
2. Use omv-firstaid to setup networking again.
I had done both before rebooting, so I can't say which method worked, but it did. I was able to complete the upgrade with the "-f" option after that. What started me down the rabbit hole was thinking that it's a good idea to upgrade a working system to the next version. During the upgrade, it killed my networking, halting the upgrade. After getting it back, my RAID played hide-and-seek with me and I lost. In fact, I lost 2TB of data. I tried getting it back through the GUI, but it would lock up every time I tried to look at the storage. Everything I read about people that have lost their RAID, had some success with getting it back using the "create" option, although there were many others I tried first. I hadn't read where that killed the RAID, but you live and learn. It may be some freakish mix of hardware and software issues, but that it was working prior to all this makes me wish I hadn't upgraded at all. I'm trying to get it back through Photorec and, though the software is great, the contents will still never be the same even if I get them back. I could spend months renaming files alone, presuming I ever knew the original name. I'm still desperately clinging to any hope of getting the RAID back in shape, but that hope is swiftly fading.