All of those errors are harmless (since there was some overlap time when neon already shipped 5.8.2, those error messages were to be expected).
The only odd one seems this:
W: Failed to fetch http://ds9-maui.s3-website.eu-central-1...._amd64.deb
Hash Sum mismatch
I assume everything went well nevertheless and if you enter the commands
sudo apt-get update
sudo apt-get upgrade
again, everything would either simply finish (minus the kio) or it would show "nothing to update"?
The only odd one seems this:
W: Failed to fetch http://ds9-maui.s3-website.eu-central-1...._amd64.deb
Hash Sum mismatch
I assume everything went well nevertheless and if you enter the commands
sudo apt-get update
sudo apt-get upgrade
again, everything would either simply finish (minus the kio) or it would show "nothing to update"?