How old until you expect a pup to bay?

I just read all of the responses. First off thanks for yall's input so far. Second, please don't turn this into a pissing match or a vs thread.

Doggie, what you said makes great sense. I haven't started that many pups, so I don't have a lot of experience to draw on. The guy said that these dogs should start early but mature late, I'm not sure what that means exactly. The sire he said didn't reach his full potential until 2 yr but was working well before then. I think I'll give them a while to settle in some more and maybe mature mentaly. They are supposed to be not only from proven parents but from proven lines. I hope they come on and prove themselves.