My opinion if there on my yard there running loose being pups my bay pen is less than 100 yards from my house if there not going and watching and showing interest by 4 months I'm loading my 22. We bay hogs constantly her the dogs are around it none stop we keep 5lb pigs on up to 175 hogs with teeth . At 6 to 7 months there in the woods finding hogs. At 2 years of age there pretty good hog dogs. But yes they are still growing and are not mature until around 3years
You sound about like my grandpa except he gives em 6 months. If they ain't finding by a year they get culled unless he just sees something in em that he likes and he gives em another 6 months to see if they come on with it finally. The old man keeps me amazed and I should probably start listening to him a lot closer than I do, he seems to keep me from getting in a bind with everything from horses and cows to the chickens we had around when I was little

lol