Specifically, the expansion will see business owners from 14 more countries, including Canada, Germany, the UK and more be able to test out the new PSTN Conferencing feature, and worldwide availability of the Cloud PBX preview, both of which were announced in July. These features will enable Skype for Business to integrate seamlessly with traditional dial-in options.
Along with the expansion, a number of new features for preview were announced. These include Number Portability for PSTN Calling, Voicemail function and new IP phone models for Cloud PBX, and a new Call Quality Dashboard. The new features however, will be limited to U.S. users.
You can sign up for the preview program here.Further reading: Microsoft, Office 365, Skype for Business