The pattern is 1= first graduating class , Next letter is the class (I placed a key in the docs, and I combined 3 letters with class and SP or DP), the following numbers are birth date (mm/dd/yy) and a unique 3 digit I’d))
Until I played one of the Carmen games from 1995 with Lynn Thigpen, and I found a note left behind from one of her agents, I didn't realize that Carmen pays her people too Lol