Static Conference Lines In the past you could work around this by scheduling an absurdly long conference call (e.g. 1000 years). In v15, you cannot schedule a conference for more than 24 hours. The reason for having such a long conference line is because 3CX does not allow recurring conferences. So organizations workaround the limitation by scheduling a 1000 year conference (I've seen this suggestion on these boards quite a few times) then make a resource in Exchange for people to schedule that line. It would be nice to have a more official way of doing this. Recurring Conferences Provide a means to create a conference call for more than one occurrence. Notify Attendees that a Conference was Canceled Currently, if the user deletes a conference call, no notification is sent to the attendees that the conference was canceled and instead the organizer has to send a separate e-mail that people may or may not read. Some attendees don't even know how to delete meetings off their calendar and this simplifies the process. I had initially request this feature but it was implemented for Web Conferences rather than audio conferences. Reference: https://www.3cx.com/community/threads/have-3cx-send-audio-conference-cancellation-notices.44973/ The lack of the first two features is the sole reason why my organization cannot upgrade to v15.