WLP001 is a higher attenuator than WLP013. When he first entered his recipe, he had not specified a yeast, so BS went with a default attenuation. When he specified his yeast on the starter tab, BS automatically added his yeast to the recipe. His yeast, WLP013 is a lower attenuator than the default that BS was using, so his FG went up and his ABV went down. If he were to sub WLP001 for 013, it attenuates better, so FG will go down and AVB will go up.