
That really flies in the face of behavioural studies where 49days is considered ideal.
http://www.doglistener.co.uk/choosing/choosing_puppy.shtm and
http://blog.betternaturedogtraining.com/2013/07/18/littermate-syndrome/"Seven to eight week-old puppies are ready to leave their mother and littermates to develop normally as individuals. I work with my clients to implement an intensive socialization program to expose puppies to a large variety of people (gold standard: 100 people before 12 weeks of age), children, places, animals, noises, bicycles, cars and so forth. Weeks 8 through 14 are the most crucial, and during this period I encourage my clients to take their puppies to as many puppy socials as feasible. Learning that there are other dogs in the world is an important part of normal social development, and play between puppies is how they learn and practice many adult behaviors and communication skills, including the "calming signals" that dogs use to diffuse otherwise fraught situations."
http://dogtime.com/puppy-when-to-bring-home-dunbar.html interestingly says what I often repeat on these threads
"For many puppies, eight weeks is the right age
Eight weeks of age has long been accepted as the optimal time to acquire a new pup. By eight weeks, sufficient dog-dog socialization has taken place with mother and litter mates to tide the puppy over until he is old enough to safely meet and play with other dogs in puppy class and dog parks. Yet the puppy is still young enough to form a strong bond with the members of his new family.
The relative level of doggy expertise in each home is a vital consideration in determining whether the puppy is better off staying longer in his original home or leaving earlier to live with his new owners. It is often assumed that breeders are experts and owners are rank novices, so that it makes sense to leave the pup with the breeder as long as possible. A conscientious breeder is usually better qualified to socialize, housetrain, and chewtoy-train the puppy. When this is true, it makes sense to get the puppy when he is older........"
I must say as my pups aren't ear tattooed until 7 weeks and I worm them at that age, and find that a few days for their tummies to settle before homing is best mine never leave until 7 1/2 weeks if that is when a weekend falls, so for me 7 - 8 weeks fits best for pups to start leaving, level of experience of new owners, individual pups forwardness etc will all play a part..
Being a numerically small breed, it is rare for pups to be homed only locally, many have long journeys which are easiest at a weekend, and as I don't6 like all pups leaving in the same week, starting them leaving just before 8 weeks allows them to all be homed by 9 or 10 weeks, if that is what suits the new owners.