Due to HMRC's rules around furloughed staff not being able to work, it was deemed necessary to suspend their email accounts (along with access to other work related systems). However due to us needing to stay in contact with staff and to make sure they didn't feel like they were totally disconnected from their jobs, we wanted to solve that a different way.
After looking into the content compliance settings a bit, it looked possible to just block them sending emails and also still allow them to use Hangouts/Chat. To do this, if you create an OU (called something along the lines of No Send), go to Apps > G Suite > Settings for Gmail > Advanced settings and select the OU you created.
Scroll down to Content compliance and select Add (or Add Another), then configure it like this...
Put a test user inside the OU, send an email to an external or internal address and you should get a bounce back that looks like this...
Hope that helps someone :)
