As stated in the beginning of this section, as long as a chat is visible to the student, they can enter that chat room at any time. Therefore, the settings for Next chat time and Repeat sessions don't open and close the chat. Instead, these settings put a time and date for the chat on the class calendar.
Chat times are listed in Calendar and in the Upcoming Events block. Note that chats are not restricted to these times; they are only announced as a way for people in the course to make a date for the chat. However, this is a good way for the teacher to announce online office hours.
Spontaneous chats have the best chance of happening if the course has a lot of students who frequent the course's ...