ubuntu-support-status shows unsupported package in official lxd images

ubuntu-support-status seems to incorrectly identify some packages as
'unsupported'. This occurs on a stock/official Ubuntu cloud image.

ubuntu-support-status
$ lxc launch ubuntu-daily:xenial status-x
$ sleep 10
$ lxc exec status-x -- apt-get update --quiet
...

$ lxc exec status-x -- ubuntu-support-status
Support status summary of 'status-x':

You have 426 packages (98.8%) supported until April 2021 (5y)

You have 0 packages (0.0%) that can not/no-longer be downloaded
You have 5 packages (1.2%) that are unsupported

Run with --show-unsupported, --show-supported or --show-all to see more details

$ lxc exec status-x -- ubuntu-support-status --show-unsupported
Support status summary of 'status-x':

You have 426 packages (98.8%) supported until April 2021 (5y)

You have 0 packages (0.0%) that can not/no-longer be downloaded
You have 5 packages (1.2%) that are unsupported

No longer downloadable:

Unsupported:
eatmydata libeatmydata1 python3-configobj python3-json-pointer
python3-jsonpatch

$ lxc exec status-x -- apt-cache policy eatmydata libeatmydata1 python3-configobj python3-json-pointer python3-jsonpatch
eatmydata:
  Installed: 105-3
  Candidate: 105-3
  Version table:
 *** 105-3 500
        500 http://archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        100 /var/lib/dpkg/status
libeatmydata1:
  Installed: 105-3
  Candidate: 105-3
  Version table:
 *** 105-3 500
        500 http://archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        100 /var/lib/dpkg/status
python3-configobj:
  Installed: 5.0.6-2
  Candidate: 5.0.6-2
  Version table:
 *** 5.0.6-2 500
        500 http://archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        100 /var/lib/dpkg/status
python3-json-pointer:
  Installed: 1.9-3
  Candidate: 1.9-3
  Version table:
 *** 1.9-3 500
        500 http://archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        100 /var/lib/dpkg/status
python3-jsonpatch:
  Installed: 1.19-3
  Candidate: 1.19-3
  Version table:
 *** 1.19-3 500
        500 http://archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        100 /var/lib/dpkg/status

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: update-manager-core 1:16.04.6
ProcVersionSignature: Ubuntu 4.10.0-22.24-generic 4.10.15
Uname: Linux 4.10.0-22-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.5
Aptdaemon:

Architecture: amd64
Date: Thu Jun 29 15:53:50 2017
PackageArchitecture: all
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 LANG=C.UTF-8
SourcePackage: update-manager
UpgradeStatus: No upgrade log present (probably fresh install)