https://github.com/danmarsden/moodle-mod_attendance/pull/210
My initial thoughts were that this should be a separate setting - allowing teachers to decide if the session should appear in the calendar, but as Brendan points out this is not how most activities work - does anyone have a real use-case for an Attendance session to be created but not shown as in the course calendar? If there isn't a proper use-case we probably shouldn't add a new setting.