Do SfB Conference IDs ever stop working?

I'm finding hard to understand, or perhaops hard to believe how the expiration of dynamic conference IDs work.

I have a business requirement for a conference bridge that is constantly available for our operational support team, when there's a major incident everyone piles into a call that matches the name of the major incident room and work until it's finished. So my need is really for a static conferenceID and meeting join link.

In Outlook if I create an all day meeting, recurring everyday for ever, I can add Skype details. By the details described here this should last for ever ! Gvien I can't test this, anyone else know ?

Also, I can create another all day, recurring everyday, Skype Meeting and get a new ConferenceID. So they both last forever.

This doesn't sound like reasonable use of one users license, so what are the limitations ?

The service description at https://technet.microsoft.com/en-us/library/mt634523.aspx states that meetings will end if the attendee list doesn't change for 24 hours. What does end mean ? Can I just dial in again the next day ? The Conference ID hasn't changed in the meeting booking.