Nextcloud SQL error while trying to upgrade from v73 to v74

[elsiehupp]

I used the standard installation method to upgrade a Mail-in-a-Box instance from v73 to v74:

curl -s https://mailinabox.email/setup.sh | sudo -E bash

But halfway through I keep getting this error:

Installing Nextcloud (contacts/calendar)...
Nextcloud is already latest version

FAILED: sudo -u www-data php8.0 -f /usr/local/lib/owncloud/occ config:app:set dav sendEventRemindersMode --value occ
-----------------------------------------

In ExceptionConverter.php line 75:
                                                                               
  An exception occurred while executing a query: SQLSTATE[HY000]: General err  
  or: 8 attempt to write a readonly database                                   
                                                                               

In Exception.php line 30:
                                                                          
  SQLSTATE[HY000]: General error: 8 attempt to write a readonly database  
                                                                          

In Statement.php line 101:
                                                                          
  SQLSTATE[HY000]: General error: 8 attempt to write a readonly database  
                                                                          

config:app:set [--output [OUTPUT]] [--value VALUE] [--update-only] [--] <app> <name>

-----------------------------------------

The weird thing is I have more than one instance of Mail-in-a-Box, and the other instance upgraded without any difficulties.

I suppose I could probably create a replacement instance and then restore from a backup, but that seems like a huge pain.

Well, I just tried moving Nextcloud to a backup:

sudo mv /usr/local/lib/owncloud /usr/local/lib/owncloud.bak

And then when I ran the update there weren't any errors.

(Yes I know this removes the Nextcloud database, but I'm 99% sure this instance wasn't actually using it, so it's safe to set aside for now.)