You might need something a little stronger 
I think @Grisu mentioned something similar above, might be worth you taking a backup copy of your current config, then upgrade to new firmware and then take a backup of the new config.
Then factory reset and apply latest backup config, reboot and see how that goes ?
might save some time and let us know if this work ?
As an interesting thought, if you had “auto update” enabled on your XT8’s, I assume this would have updated your XT8’s automatically and by passed the factory reset advise given in the changelog 
In a completely sane world, madness is the only freedom (J.G.Ballard).
You need to login in order to vote