Hi, your bully is 10 months old, so he is old enough for adult food. You can switch to adult food at 6 or 7 months old. Blue Buffalo is a great food, so if he's doing well on this food you don't have to switch. A lot of people on here including myself feed Fromms Beef Frittata to our bullies, it is a high quality food as well, and is an all stages food as well. It comes in 4 different adult formulas. A lot of bullies are allergic or sensitive to chicken, so the beef is good for them. My female Blossom is allergic to Chicken and salmon, so we feed the beef. Both my two do well on this food, and they get 1 cup of kibble in the morning, and I. The evening they get 1 cup of home cooked. We also give them yogurt, cut up apples, bananas, strawberries, blueberries, cheese strings, and cottage cheese as treats. They also get salmon oil in their kibble, and apple cider vinegar in their drinking water everyday.