Deer Run Farm replaces half of their flock every year with new pullets. The "retirees" are birds that are just turning 2 years old. Although not at their highest production peak, they will still continue to lay at a decent rate for backyard birds. These birds were used as breeding stock and could very well continue to be should a buyer want to breed with them.
Most available girls will likely be in a stage of molting when purchased this time of year. This means they won't look perfect. They'll likely be missing feathers from shedding them or they'll have ruffled feathers from the exposure to the males within the flock. Given time to finish their molt and acclimate to their new homes, they'll re-feather out just lovely.
Keep in mind that these birds have been 100% free range on pasture since they were 5 months old and selected as breeders. It may take some time for them to get used to a smaller coop and run.
Always remember for your own flock's safety and for the safety of your new birds to quarantine for 30 days before integrating them into your flock. Also note that when integrating your new birds may not lay again until they're comfortable with their new home and other hen-mates. Integration is best if done at night when birds are sleeping and have poor eye sight. This allows them to wake up to one another in the morning as if they've always been together.