When the following update commands are run in the Proxmox version 6 series;
apt-get update
apt-get upgrade
apt-get dist-upgrade
while the 3 update commands above are being run, an error like the following may occur.
N: Repository 'http://security.debian.org/debian-security buster/updates InRelease' changed its 'Suite' value from 'stable' to 'oldstable'
N: Repository 'http://deb.debian.org/debian buster InRelease' changed its 'Suite' value from 'stable' to 'oldstable'
N: Repository 'http://deb.debian.org/debian buster-updates InRelease' changed its 'Suite' value from 'stable-updates' to 'oldstable-updates'
The command that needs to be run to fix the issue;
apt-get update --allow-releaseinfo-change