i am getting 11 new hens today. one is 2 years old and the rest are between 8 months and 1 year. my existing 4 hens are a year old. i am already getting the hens in the late evening, just not sure the etiquette on introducing them. we have a large coop and an extremely large run for them. we do have the option of having the pre existing flock free range in our fenced back yard. any tips?