Only active courses in directory

As of now there is an option to exclude taken/expired courses from the directory. It only influences logged in students, and only works with online courses. How to hide offline courses with passed date from directory? I know, it is impossible at this point of WPLMS. We even have no course field for offline course start date/duration to calculate the course end date. But I guess the directory loop uses the same thing with expired online courses field. So, which php files should I alternate in order to filter the directory (assuming that I already have all the necessary fields for the offline courses? I'm also adding this to the future requests, as it complements the expired online courses feature, and one day WPLMS will be ready for this.