mDNS name changed with 4.13 OS update

I updated the OS 4.13 on my Pi 4 about 6 hours ago.

Since then all of the sensor devices that were reporting data via MQTT can not connect to the mosquitto server. Those I checked are reporting rc=2 (Connection Refused: Identifier rejected)
The connection and all the devices were working properly before the update.

I can still send commands to devices that listen to MQTT and respond.
I restored backups from before the upgrade, but it does not restore the older OS version.
Please advise what to check or do.

EDIT:
I just checked the assesscontrollist is unchanged. The user still has permissions.

EDIT2:
The Supervisor -> Host System -> Hostname is still “hassio”.
But my devices trying to connecting to “hassio.local” no longer connect.

What has to change to put this back like it was?

EDIT3:
semi solved:
Conclusion from above: mDNS is not working correctly…
run

avahi-browse -alr

and find that on mDNS the system is now “hassio-2”

How do I set it back to “hassio”???

EDIT4:
Since I have seen nothing here about how to repair this, I decided to blow the system away ad restore it from a backup.
When I mounted the SD on my laptop to re-write it, the volumes on the card were opened in file browser windows. As usual, there were partitions for hassos-data and hassos-overlay.
There was mounts for hassos-kernel and hassos-kernel1… I guess a new kernel with the 4.13 upgrade.

But instead of a single “disk” being mounted, there were two. disk and disk1.

Is it possible this is way my hassio.local has become hassio-2.local?

EDIT5:
I didn’t hear anything better from the community, so I reloaded my system.
I re-flashed the SD card with the latest .iso (3.14) and restored from the backup I made just before the 3.14 upgrade.
My system is back and running.

Thanks,
-Mike

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