Error updating snaps

I just got kicked out of an lxc container I was using. I can’t do anything with lxc now:-

 alan@hal:~$ lxc list
LXD socket not found; is LXD installed and running?
alan@hal:~$ snap version
snap    2.30
snapd   2.30
series  16
ubuntu  16.04
kernel  4.10.0-42-generic
alan@hal:~$ snap info core
name:      core
summary:   snapd runtime environment
publisher: canonical
contact:   snappy-canonical-storeaccount@canonical.com
description: |
  The core runtime environment for snapd
type:        core
snap-id:     99T7MUlRhtI3U0QFgl5mXXESAiSwt776
tracking:    candidate
installed:   16-2.30 (3748) 87MB core
refreshed:   2017-12-18 15:13:21 +0000 UTC
channels:                                  
  stable:    16-2.29.4.2            (3604) 87MB -
  candidate: 16-2.30                (3748) 87MB -
  beta:      16-2.30                (3748) 87MB -
  edge:      16-2.30+git476.f91a849 (3772) 87MB -

Looking at what’s updated recently: (with some lines redacted)

1518  Error   2017-12-21T10:51:25Z  2017-12-21T10:52:10Z  Auto-refresh 4 snaps
1519  Error   2017-12-21T12:17:10Z  2017-12-21T12:17:11Z  Auto-refresh snap "gnome-taquin"
1522  Error   2017-12-21T18:47:12Z  2017-12-21T18:47:26Z  Auto-refresh snaps "gnome-taquin", "snapcraft", "lxd"

Looking further:

alan@hal:~$ snap change 1518
Status  Spawn                 Ready                 Summary
<snip>
Done    2017-12-21T10:51:25Z  2017-12-21T10:52:03Z  Run configure hook of "boa" snap if present
Done    2017-12-21T10:51:25Z  2017-12-21T10:51:26Z  Ensure prerequisites for "gnome-taquin" are available
Error   2017-12-21T10:51:25Z  2017-12-21T10:51:26Z  Download snap "gnome-taquin" (14) from channel "edge"
Hold    2017-12-21T10:51:25Z  2017-12-21T10:51:26Z  Fetch and check assertions for snap "gnome-taquin" (14)
<snip>
2017-12-21T10:51:26Z ERROR received an unexpected http response code (401) when trying to download https://api.snapcraft.io/api/v1/snaps/download/pyEMtK4uVBGIvCV2B1NHC1sb3c2bL7x6_14.snap

That last snap ID error line happens to be gnome-taquin.

Why has a 401 error come from the store, and why has it broken other snaps?

Seems my lxd is broken, so I started a conversation on their forum

All fixed by a change upstream in lxd.