To ensure that all users retain their current phone numbers once the migration to Microsoft Teams Calling Plans is complete and to minimize the downtime of PSTN features, the first step is to schedule a port order for the phone numbers of all the users. This process transfers the existing phone numbers from the current PSTN provider (used with Skype for Business Server) to Microsoft Teams. This is essential to maintain continuity and prevent service interruptions.
To deploy Direct Routing with Office 365 E3, users need the Microsoft 365 Phone System license. This license enables PBX capabilities and allows integration with your telephony system, which is essential for Direct Routing. The other options provided are either irrelevant to Direct Routing or additional services that would not fulfill the core requirement to enable the feature.
To ensure the employee can send meeting invitations with a dial-in conferencing bridge that uses a local number in Lisbon, the first action you need to perform is to edit the Audio conferencing settings of the employee in the Microsoft Teams admin center. This allows you to change the toll number to a local Lisbon number specifically for this employee. Additionally, since the Microsoft 365 E3 license does not include Audio Conferencing by default, you need to assign an Audio Conferencing add-on license to the employee from the Microsoft 365 admin center. This add-on license enables the necessary audio conferencing capabilities for the employee.


To prevent a specific user from calling international phone numbers from within a Microsoft Teams meeting, you should assign a dial-out policy to the user. Assigning a dial-out policy allows you to control and restrict the numbers that users can dial out to, including preventing international calls. This policy can be set in the Audio Conferencing settings for the user or through PowerShell with the Grant-CsDialoutPolicy command.