A. SCCM has two types of management license for non-server OS environments—OSE management licenses (one OSE for each OS, which can be used by multiple users) and user management licenses (one user management license for each user, allowing all devices assigned to the user to be managed by SCCM).

If your users currently have SCCM user management licenses, their mobile devices can be managed by SCCM without additional licenses. If OSE management licenses are currently assigned to the desktops, additional OSE management licenses will be required for the mobile devices, unless you can switch to user management licenses. (This will also be the case if mobile devices need to be managed for users that don't have a SCCM-managed desktops.)