Introduction
Open the Skype for Business app and tap your profile picture. Navigate to Call forwarding > Simultaneously Ring. Choose the desired number.
Instructions
1) Open the Skype for Business application.
2) In the top left-hand corner, tap your profile picture (avatar).
3) Tap Call forwarding.
4) Tap Simultaneously Ring.
5) Choose an existing number, or tap New Number to type a new phone number.
Outcome
Incoming calls to your DID number will ring simultaneously at the number you have chosen plus in your Skype for Business client wherever you are signed in.