My running team suspended group workouts for the foreseeable future. The guidance we were given was that maintaining your base is the best thing you can do right now, since it's not looking great that spring races will happen. We were told to do ~80-90% of our peak mileage but slower (0:45-1:00 per mile slower than race pace). So for the marathoners out there, keep runs longer and slower and get used to mileage. The speed work isn't critical until races pop back up, but get about 1-2 workouts a week in at your tempo/threshold paces and throw in some strides to remember what it feels like to go fast