The @ symbol does not mean the same in the online game as does in the board game with the advanced fatigue in place. Ignore the @ symbol.
Fatigue is based on pitch count resulting in an F? rating for fatigue. As that number decreases the computer engine makes adjustments which are adjustments in the dice rolls in an unknown manner. Might be a higher percentage of rolls going to the hitter cards. To my knowledge the details have never been revealed to us and doubt they ever will.