They have all only done so within the past 7-10 days. My guess is that it takes a bit of time to implement the systems, do the training, test it and then go "live."
This is pretty good. Yes, it's possible to defraud the system, but there is just so much effort that can be put into this and the ante has just been upped because it's a DOT form and a false statement is a felony. Not that everyone with a an emotion support vole needs to go to prison, but people tend to think a bit more.