Udemy

Yes. And I have added and/or replaced entire sections of a course.    I think it is important to update your courses when there is new knowledge in your field. This keeps your course relevant. For example, in the last year or two I have added sections to several of my courses on leading/facilitating remote teams, an issue that did seem important five years ago.    ... View more

Not automatically. You'd have to create a new course or expand an existing one, adding in the new sections and lectures and re-uploading the videos. Then unpublish the smaller courses you consolidated if you wish. Students seem to like comprehensive courses, so this isn't a bad strategy IMO.   ... View more