2 Firewalls - Strange issue during upgrade of one of them (tar: Damaged tar ...)

[TheZeke]

I have two opnsense firewalls in a production environment. I upgraded the second one (UI 64.x.x.12) first and all went well.  While upgrading the first one (UI 64.x.x.11) to 18.7 however a strange thing happened.  These are both VMs running under Xen.

1.) After the upgrade the GUI said ***REBOOT*** but didn't reboot.  I waited for several minutes but it did not reboot on it's own like the other one did.
2.) I soft booted the VM manually and it shutdown nicely and rebooted without issue.
3.) During the upgrade process it rebooted itself a few times after applying patches/upgrades.
4.) During the final phase of the upgrade I got a strange issue..  It said the following repeatedly:
    tar: Damaged tar archive
    tar: Retrying...
    tar: Damaged tar archive
    tar: Retrying...
    tar: Damaged tar archive
    tar: Retrying...
5.) I quickly took a screenshot so I could remember the exact wording of the messages
6.) For a laugh I hit ctrl-C on the console of the VM
7.) It loaded some stuff during the boot but then dropped to a console
8.) I rebooted it again (by typing 'reboot')
9.) The same thing happened where it kept looping saying "tar: Damaged tar archive" repeatedly.
10.) I hit ctrl-C again and it finished booting and is now up and working.

During this whole ordeal the secondary firewall took over operations successfully so there was no hit on service.

I logged into the GUI and all seems to be well but I don't want to perform the updates to 18.7 now because I don't know what's going to happen during the reboot.  I took a backup (encrypted) of the configuration for safe keeping.

So my questions are:
1) Should I do the updates and see what happens?
2) Can I fix this 'tar: Damaged tar archive' thing before I reboot it again and then do the updates?
3) Should I just reinstall it and then apply the configuration backup to a fresh install?

What's the best course of action here?

Screen shot attached.