Comment 5 for bug 1930741

I can confirm that this bug is fixed in the proposed 27.2.1 package on Xenial, Bionic, Focal and Hirsute by using the following script:

----------------------
#!/bin/sh
set -x

series=xenial
name=$series-check

lxc delete --force $name
lxc launch ubuntu-daily:$series $name

lxc exec $name -- sudo sh -c "cat <<EOF >/etc/apt/sources.list.d/ubuntu-$series-proposed.list
## Enable Ubuntu proposed archive
deb http://archive.ubuntu.com/ubuntu/ $series-proposed restricted main multiverse universe
EOF"
sleep 10
lxc exec $name -- sh -c "sudo apt-get update > /dev/null"
lxc exec $name -- sh -c "sudo apt-get install aptdaemon -yq > /dev/null"
# Verify that the output shows only:
# dict_keys(['apt::install::post-invoke-success', 'apt::update::post-invoke-stats'])
lxc exec $name -- python3 -c "
from aptdaemon import config
c = config.ConfigWriter()
uataptconf = open('/etc/apt/apt.conf.d/20apt-esm-hook.conf')
lines = uataptconf.readlines()
print(c.parse(lines).keys())
uataptconf.close()
"

lxc exec $name -- sh -c "sudo apt-get install ubuntu-advantage-tools -yq > /dev/null"
lxc exec $name -- ua version

# Verify now that the output shows:
# dict_keys(['apt::install::pre-invoke', 'apt::install::post-invoke-success',
# 'apt::update::post-invoke-stats', 'aptcli::hooks::upgrade'])
lxc exec $name -- python3 -c "
from aptdaemon import config
c = config.ConfigWriter()
uataptconf = open('/etc/apt/apt.conf.d/20apt-esm-hook.conf')
lines = uataptconf.readlines()
print(c.parse(lines).keys())
uataptconf.close()
"

set +x
--------------------------------

This issue is already fixed on impish since release 27.1~21.10.1.1