Comment 4 for bug 1921820

I retried after the recent changes using a 20.04.2 image and doing a manual update,
but still see the error/crash, but I'm now able to re-login afterwards.
And that allowed me to complete the installation and also to gather the logs and crash files:

...
Installer shell session activated.

This shell session is running inside the installer environment. You
will be returned to the installer when this shell is exited, for
example by typing Control-D or 'exit'.

Be aware that this is an ephemeral environment. Changes to this
environment will not survive a reboot. If the install has started, the
installed system will be mounted at /target.
root@ubuntu-server:/# snap list
Name Version Rev Tracking Publisher Notes
core18 20201210 1945 latest/stable canonical* base
lxd 4.0.5 19189 4.0/stable/… canonical* -
snapd 2.48.2 10704 latest/stable canonical* snapd
subiquity 21.01.2 2278 latest/stable/… canonical* classic
root@ubuntu-server:/#
root@ubuntu-server:/# snap refresh subiquity --channel=edge/mwhudson-hack
subiquity (edge/mwhudson-hack) 0+git.de29ffe0 from Canonical* refreshed
root@ubuntu-server:/# generating crash report
report saved to /var/crash/1617171065.612380743.ui.crash
Traceback (most recent call last):
  File "/snap/subiquity/2278/usr/bin/subiquity", line 33, in <module>
    sys.exit(load_entry_point('subiquity==0.0.5', 'console_scripts', 'subiquity-tui')())
  File "/snap/subiquity/2278/lib/python3.6/site-packages/subiquity/cmd/tui.py", line 142, in main
    subiquity_interface.run()
  File "/snap/subiquity/2278/lib/python3.6/site-packages/subiquity/client/client.py", line 326, in run
    super().run()
  File "/snap/subiquity/2278/lib/python3.6/site-packages/subiquitycore/tui.py", line 338, in run
    super().run()
  File "/snap/subiquity/2278/lib/python3.6/site-packages/subiquitycore/core.py", line 136, in run
    raise exc
  File "/snap/subiquity/2278/lib/python3.6/site-packages/subiquitycore/context.py", line 148, in decorated_async
    return await meth(self, **kw)
  File "/snap/subiquity/2278/lib/python3.6/site-packages/subiquity/client/controllers/progress.py", line 79, in _wait_status
    cur=self.app_state)
  File "/snap/subiquity/2278/lib/python3.6/site-packages/subiquity/common/api/client.py", line 49, in impl
    return serializer.deserialize(r_ann, await resp.json())
  File "/snap/subiquity/2278/lib/python3.6/site-packages/subiquity/common/serialize.py", line 131, in deserialize
    return self._deserialize_attr(annotation, value, metadata, path)
  File "/snap/subiquity/2278/lib/python3.6/site-packages/subiquity/common/serialize.py", line 121, in _deserialize_attr
    field, value[field.name], path))
  File "/snap/subiquity/2278/lib/python3.6/site-packages/subiquity/common/serialize.py", line 114, in _deserialize_field
    field.type, value, field.metadata, path)
  File "/snap/subiquity/2278/lib/python3.6/site-packages/subiquity/common/serialize.py", line 138, in deserialize
    return getattr(annotation, value)
  File "/snap/subiquity/2278/usr/lib/python3.6/enum.py", line 326, in __getattr__
    raise AttributeError(name) from None
AttributeError: CLOUD_INIT_WAIT
Connection to 10.245.236.26 closed.
fheimes@T570:~$

# after re-login

root@ubuntu-server:/# snap list
Name Version Rev Tracking Publisher Notes
core18 20201210 1945 latest/stable canonical* base
lxd 4.0.5 19189 4.0/stable/… canonical* -
snapd 2.48.2 10704 latest/stable canonical* snapd
subiquity 0+git.de29ffe0 2334 latest/stable/… canonical* classic
root@ubuntu-server:/#