I interviewed with Maryland SDOS mid January and I am currently on my POI's waitlist. From what they told me, they will be holding an in-person visit day this month with a few select applicants. I was told by my POI that they will probably only be accepting 2 students, so this has been an extremely competitive cycle. I have not heard from Penn State (but I know someone who has) and they will be holding an interview weekend this month with all of their top applicants. These applicants have already been notified. As for Clemson, I haven't heard from them directly, but my POI did set up a phone call with one of my recommenders last week (make of that what you will).