A thought which comes out of the Firearms Academy of Seattle - Marty Hayes tree of training is that if you ever have to use a FA, you are better served if you have a paper trail of training, and re-training. Legal requirements, Proficiency with the weapon used, and Perhaps especially in the Threat identification - ie: Is that dog threatening, fearful, or playful? One way is to keep those paper certificates when you take courses. And the associated receipts. How else is anyone tracking this?