1-4-2. CRITERIA c. Three-letter identifiers are assigned to aircraft operating agencies which operate 7 or more non-seasonal international air operations per week and/or generate the appropriate flight movement messages and other related flight operations over the Aeronautical Fixed Telecommunications Network (AFTN); or, 15 or more non-seasonal domestic commercial round trip air operations per week. Aircraft operating agencies which generate less than the prescribed international and/or domestic flight operations, may be waived as deemed advantageous to the U.S. air traffic control system and operationally appropriate by FAA. Exceptions to the above criteria may be authorized on an individual basis.
I don't think this would qualify as 15 "non-seasonal domestic commercial
round trip air operations per week" either...
Not sure exactly what constitutes an exception that has a chance of being approved though. Perhaps something similar to the ACA could be done for all pet/animal rescue related services as a whole, including Pilots N Paws? I think that may be "advantageous to the U.S. air traffic control system".
(I'm just reading and thinking about loud...I don't know much about this.)