:~# apt install --reinstall docker.io=20.10.12-0ubuntu2~18.04.1
Reading package lists... Done
Building dependency tree
Reading state information... Done
	[...]
Need to get 0 B/31.8 MB of archives.
After this operation, 8,033 kB of additional disk space will be used.
Preconfiguring packages ...
(Reading database ... 165543 files and directories currently installed.)
Preparing to unpack .../docker.io_20.10.12-0ubuntu2~18.04.1_amd64.deb ...
The aufs storage-driver is no longer supported.
Please ensure that none of your containers are
using the aufs storage driver, remove the directory
/var/lib/docker/aufs and try again.
dpkg: error processing archive /var/cache/apt/archives/docker.io_20.10.12-0ubuntu2~18.04.1_amd64.deb (--unpack):
	new docker.io package pre-installation script subprocess returned error exit status 1
Errors were encountered while processing:
	/var/cache/apt/archives/docker.io_20.10.12-0ubuntu2~18.04.1_amd64.deb
E: Sub-process /usr/bin/dpkg/ returned an error code (1)

:~# apt upgrade docker.io
Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt --fix-broken install' to correct these.
The following packages have unmet dependencies:
	containerd: Breaks: docker.io (< 19.03.13-0ubuntu4) but 18.09.7-0ubuntu1~16.04.7 is installed
E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).