Incoming calls to your business phone number are sent out to a group of your account users, allowing any available user the opportunity to answer the call.
After a short message is played to the users, they can accept the call by pressing "1" on their keypad. Once the call is accepted, ringing stops for all the other users in the group and the accepting user is connected to the call.
Setup your number to forward calls to your new group.
As the first user accepts the call, ringing will stop for all the other users.
You can create multiple groups from your account users and assign those groups to different phone numbers. Users can be in more than one group.