My KPA was at 1.8.0 prior to attempting to upgrade it tonight. I put the upgrade file on the same USB in the same directory as always. I turned the Kemper on and got distracted with other studio stuff while it booted and I totally forgot about it. When I finally remembered, I looked at the display and it was not prompting me to do an upgrade like it has in the past. So, I decided to shut it down and try again ... this time with my full attention. As it came back up I saw that the OS had reverted back to 1.6.1...holy smoke, what the heck happened? It came fully up and did not ask to upgrade. Wow, this was strange. Where the heck did 1.6.1 come from. Anyway, I shut it down again, waited a moment and the turned it on again. As it came up it again displayed the OS version as 1.6.1 After it was fully back up it finally displayed the upgrade message. I responded with yes and it completed the upgrade successfully...thank goodness.
Anyway, I thought I'd share this little bit of strange behavior in case someone else is confronted with same thing.