We don't use an attendant during business hours. Calls ring through live. But we use an attendant at night. On our old on-prem system, we had an easy button on everyone phone to toggle "Night Mode" between our standard call queue setup and the attendant.
In addition to making it easier to switch (we have non standard hours, so a schedule doesn't work), it also provided a visual queue since the button was lit up red when Night Mode was on.
It would be nice to be able to do this with RingCentral hardware phones like our T54Ws.