What will happen when a user tries to join a webinar that is full?

If you are the webinar host, you will not get any message during your presentation. It's suggested that you upgrade your U
Webinar plan to allow more webinar participants prior to the webinar broadcast.  

If you are the user who is trying to join a webinar that is full, you will get a message "The webinar is full". You can only wait for someone to leave the webinar before you can join.