Diana Boling

I have 2 Rodigan Ridgebacks and a small mixed schnauzer mix. The two ridgebacks are mother and son. Mom is about 10 and son is about 5. The son's name is Ricky. Ricky has been a great dog and usually friendly when he knows someone or if I am around. They are all off leash dogs but there are times when people come to our property to work or to participate in Bible studies. For years Ricky would bark if he didn't know the person and most are afraid to approach without us because of his size. Recently he has taken to jumping and biting people even when I am with him. This does not work for us because we have no fences and I don't want to keep such a big dog tied up or inside all day. I just purchased the program but I don't know if I should start trying to correct the behavior or start the courses from the beginning. He obeys my commands when calm but if he sees another dog on the property he bolts after it and unless I yell at him a number of times (probably not the best I know) he takes a while to return to me when he is aggressive toward people. Should I start from the beginning or is there a place I can start to stop the biting behavior?