While running upgrade I ran into the same issue on a Protectli device.
I only stopped the service "syslogd Legacy Syslog Daemon" which also sopped the service "syslog-ng Syslog-ng Daemon".
Once both of the services were stopped the upgrade ran the rest of the way without issue.
I only stopped the service "syslogd Legacy Syslog Daemon" which also sopped the service "syslog-ng Syslog-ng Daemon".
Once both of the services were stopped the upgrade ran the rest of the way without issue.