What is the most logical next event?

How to know when to stop breeding a male dog 
Consider your dog's age. 
When deciding whether your dog should continue breeding, think about how old he is. Most male dogs can breed until they are senior dogs, but it is difficult for older dogs to get females pregnant.
After your dog is around 10 years old, you may want to stop breeding him. Some believe that certain small breeds shouldn't be bred after age seven, while other breeds can be bred up to age 12.