I suggest you contact whomever that authority is and let them know that the shelter violated the same law by issuing an incorrect STERILIZATION AGREEMENT
Having done volunteer work in shelters, people come up with all sorts of excuses as to why they don't spay/neuter/vaccinate the animals they adopt. Shelter folks have to deal with this sort of thing all the time.
Frankly, if you get the citation, ignore it. If it comes down to a court hearing (unlikely), bring the evidence you have from your vet as to why the surgery could not be performed within the required time period after adoption.