Sensitivity Labels, specifying trusted domains using OutlookJustifyTrustedDomains?

I've created several Sensitivity Labels and marked them as requiring justification to send to untrusted domains.

Now I want to define the domains which ARE trusted and bypass justification prompt using Set-LabelPolicy -Identity "Global" -AdvancedSettings @{OutlookJustifyTrustedDomains=" ..."}

Does this option imply subdomains are also trusted? In other words would -

Set-LabelPolicy -Identity "Global" -AdvancedSettings @{OutlookJustifyTrustedDomains="contoso.com"}

mean that emails to sales.contoso.com, finance.contoso.com etc. would NOT generate a justification prompt?

Also where can I report on the justifications users have input?