A user named User1 selects Forward my calls, and all incoming calls are forwarded to voicemail as shown in the following exhibit. You need to ensure that User1 can change the destination of the…

Busy on busy controls call behavior when a user is already on a call but does not govern the ability to set or change call forwarding destinations.

Enterprise Voice is the Teams capability that enables full PSTN calling features, including the ability for users to set and change call forwarding destinations such as external phone numbers or other users. Without Enterprise Voice enabled, call routing configuration options are restricted and users cannot modify forwarding targets beyond basic voicemail. Enabling it unlocks the complete call control settings in the user's Teams calling settings.

Outbound calling permissions control whether a user can place outbound calls but do not affect the ability to configure inbound call forwarding destinations.

Simultaneous ring causes calls to ring on multiple endpoints at once but does not enable changing the forwarding destination setting.