The student had not returned for the FREE basic refresher. Every year is not unrealistic. Ask your training program if they will offer you FREE refreshers. I can't imagine not doing it that way if you care about your students. The same applies to safety training.
Shooters bemoan the thought, but every few years a very basic gun safety class is a great idea.
Shooters do not want to pay money for training that isn't fun and exciting. Maybe it is our desire to be in movie like situations, or a little Walter Mitty in all of us. The gun training community keeps dodging important issues. So basic, so easy to do if you think about it. Perhaps we don't want to know that information, because I will tell you NOW that there is NO connection between range proficiency and survival.