When you enable 'do not disturb’:
Calls to you are redirected to voicemail if available. Otherwise, the callers hear busy tone.
People calling from numbers in your 'do not disturb' exceptions list can still call you and forwarding can still be applied to these calls.
Calls to any hunt group of which you are a member are no longer presented to you (unless you are the last available member of the group).
Call already alerting your phone are not affected and continue alerting.
You can still use the phone to make outgoing calls. When you go off-hook you hear interrupted dial tone.
Do Not Disturb – This icon indicates that you have do not disturb enabled.