Well, I am new to all this... and just studying and researching... I can definitely see what your saying about the age... Prob. people say to wait till the second heat is because normally they have the first heat earlier

so then by the
age 2 they usually have there second heat.
I promise, I wasn't putting anyone down... just giveing the little bit of knowledge I have read on and other breeders have said to me. But I am sure there are always some exceptions to the rules