[troubletb]

Well, I'll try to help answer some questions.
First like you said some will stay black and tan. This is true, but most (in my case anyway) will change and the changes will occur for years. Look at the roots, you can usually tell is there will be a change by the root color. My Petey is black and tan, and he is 8 months old now, he still has more black then I wish he had, but I'm still hoping that it will turn. My Bell and Lilly both born black and tan are now blue and gold. Bell is much lighter then I wish she were but at 3 yrs old she is still changing. When I brush Lilly you can actually see growth line in her hair. black, blue, silver black and so on. its very odd looking. Lilly's hair is very soft on her head and some what wiry on her back. But as she is only 9 months old I know her coat is also still changing.

Also the coat will take years to grow to its full length. I never cut petey's hair and at 8 months old its about 4" from the ground. But he is very small. Lilly'sis slower growing and I doubt her coat will ever be floor lenght. This is my Petey, notice all the black where there should be tan/gold. I'm still hoping that it will change

Hope some of this helped.