I am the director of a dog rescue. We will not do adoptions from 12/15 until 1/10 because they usually do not work well. When adopting a dog it should have stability in the first month and during the holiday's it is very hard to do. Plus, with all the people coming in and out during the holidays it will mess with the training of the dog.
There are also so many people that impulse buys that end up not wanting the dogs in February. You have no clue how many dogs come into rescue that month
JMO