How do breeders determine what color to put on the registration when the puppy is black and brown? Our dogs breeder gave us her papers and forgot to mark the color and I have no idea what to put

I am new to the breed and there is so much to learn. We just got our little girl Grace yesterday and she is such a sweet little thing. She is 11 weeks old and she started getting a little lighter on the top of her head - not much yet. I just don't know what to expect from her at all after reading some of the posts on here. Compared to her brother she has straight full hair, he had wavy full hair. So I don't know what that means for her. Grace's mother was light grey and tan with a darker gold (?) face as was her grandmother. So should I wait to until she is older and has changed colors before I send in her papers so that they are accurate?