We've run into some issues with several of our CSCE classes filling up in the Fall (we already have large waiting lists in some classes), and many of the slots have been taken by graduate EE/CE students (as an example 1/3 of the seats in our CS 470 course (Distributed Data Retrieving, or "Big Data" class) are currently taken by graduate EE and CE students). We've also had big problems with students registering for classes to try them out, then dropping ones they don't want. This has led to many wasted seats that we haven't been able to fill at the last minute.
I don't have a way to contact your students directly, so I'm wondering if you can pass on the following info. There are two main policies that we will be following, both of which will affect EE/CE grad students enrolled in CS classes.
1) For undergraduate classes (400 level), undergraduate students are given priority. For any undergraduate class in which there are undergraduates on the waiting list, graduate students will be dropped from the course to make room for undergraduates.
2) For graduate classes in which we need room, we will drop graduate students currently registered for more than 10 hours of courses (more than 3 courses per semester). So, if grad students want to ensure they stay enrolled in a graduate class, they should make sure they are registered for no more than 10 hours.