Hi @pturmel, thank you very much for your always prompt and accurate responses. I will contact our local IA representative here in Australia and plan for an upgrade to the next LTS version.
In between, I found a workaround. I noticed that the launcher that comes on version v8.1 opens the v8.0 project even when the backup server is down. Hopefully, this palliative solution will not bring more harm than good.
Just to illustrate what we have now:
10 clients (HMIs) in the automation network have access to both Ignition servers and are using the Vision Client Launcher v1.0.17.
Intermittent remote clients (initiated and terminated by users) in the corporative network are using the Vision Client Launcher v1.1.7
The customer intends to fix the infrastructure problem that caused the backup server to lose connection to the corporative network in the coming days.