They live answer during the day. In night mode, they go to a CRA, play a greeting where callers can either leave a message in the general mailbox or are forwarded to an on-call phone via transfer to a phantom. When it stops working, callers hear nothing or possibly a beep, and are disconnected. We managed to sell them SWA so we can run this by tech support, but seeing as they're on 6.1.4 currently, I'm upgrading them to the latest release first.