I have the same issue on 16.04.6 even:
root@VA2ZVP4CKH01:~# apt dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following packages will be upgraded:
base-files containerd.io docker-ce docker-ce-cli python3-distupgrade python3-update-manager telegraf
ubuntu-release-upgrader-core update-manager-core
9 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 19.8 MB/106 MB of archives.
After this operation, 6,128 kB disk space will be freed.
Do you want to continue? [Y/n] y
Err:1 https://download.docker.com/linux/ubuntu xenial/stable amd64 containerd.io amd64 1.2.10-2
404 Not Found
E: Failed to fetch https://download.docker.com/linux/ubuntu/dists/xenial/pool/stable/amd64/containerd.io_1.2.10-2_amd64.deb 404 Not Found
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?
root@VA2ZVP4CKH01:~# cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=16.04
DISTRIB_CODENAME=xenial
DISTRIB_DESCRIPTION="Ubuntu 16.04.6 LTS"