MiVB Console and 5550 Console works the same way, will not turn to Day mode if there's no headset connected.
Or if the headset is unplugged, will auto switched to Night Mode.
The best way to get around this as @Billz66 has said, create a new tenant, make the Night Service Leader to be the tenant itself, and assign the Console to this.
Allow Permission to all other tenants and vise versa. This will make sure if the console goes to Night Service accidentally, the system remains in Day Mode.
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