Problem upgrading 4.1 -> 4.2 with "no-subscription" repository

When trying to upgrade to 4.2 using the "no-subscription" repository I get this error:

root@pve:~# apt dist-upgrade -y
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
2 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Setting up pve-manager (4.2-4) ...
Job for spiceproxy.service failed. See 'systemctl status spiceproxy.service' and 'journalctl -xn' for details.
dpkg: error processing package pve-manager (--configure):
subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of proxmox-ve:
proxmox-ve depends on pve-manager; however:
Package pve-manager is not configured yet.

dpkg: error processing package proxmox-ve (--configure):
dependency problems - leaving unconfigured
Errors were encountered while processing:
pve-manager
proxmox-ve
E: Sub-process /usr/bin/dpkg returned an error code (1)​

Also relevant:

root@pve:~# systemctl status spiceproxy.service
● spiceproxy.service - PVE SPICE Proxy Server
Loaded: loaded (/lib/systemd/system/spiceproxy.service; enabled)
Active: failed (Result: exit-code) since Tue 2016-05-10 18:47:20 EDT; 12s ago
Process: 2573 ExecStart=/usr/bin/spiceproxy start (code=exited, status=255)

May 10 18:47:20 pve spiceproxy[2573]: start failed - unable to create socket - Address already in use
May 10 18:47:20 pve spiceproxy[2573]: start failed - unable to create socket - Address already in use
May 10 18:47:20 pve systemd[1]: spiceproxy.service: control process exited, code=exited status=255
May 10 18:47:20 pve systemd[1]: Failed to start PVE SPICE Proxy Server.
May 10 18:47:20 pve systemd[1]: Unit spiceproxy.service entered failed state.​

I made sure all VMs were stopped before attempting the upgrade, the subscription repository is also disabled (I don't have a key for this install yet).

Is anyone getting the same? I am not familiar enough with Spice to debug this right away and I thought I'd ask first here. I'll share my findings here when I get around to digging further into this.
 

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