Comment 2 for bug 2008280

further investigation based on rev 2959:

- commenting out self._get_ua_security_status() in UpdateManager.refresh_cache appears to resolve this (this would appear to confirm that this revision is the cause)

- it would appear that calling updates() (imported from uaclient.api.u.pro.packages.updates.v1) in UpdateManager._get_ua_security_status is 'messing' with update-manager

- adding a print(apt_pkg.config.dump()) before and after update_result = updates() in UpdateManager._get_ua_security_status shows (diff only)
BEFORE updates():
Dir "/";
Dir::State::status "/var/lib/dpkg/status";
Dir::Bin::dpkg "/usr/bin/dpkg";
AFTER updates():
Dir "/var/lib/ubuntu-advantage/apt-esm";
Dir::State::status "/var/lib/ubuntu-advantage/apt-esm/var/lib/dpkg/status";
Dir::Bin::dpkg "/var/lib/ubuntu-advantage/apt-esm/usr/bin/dpkg";
This would seem to confirm interference with update-manager when calling calling updates() from ubuntu-advantage-client. There might of course be other interferences as well.