D issued what it labeled as an Intermodel Order. That order forth the conditions under which wireline telecommunications carriers must transfer telephone numbers to wireless carriers. D claimed the order was interpretive but nonetheless published it in draft form and invited comments. Ps challenged the rule in that D failed to comply with the Regulatory Flexibility Act (RFA). D contends that its order is an interpretative rule a rule that merely interprets one of D's previous legislative rules and hence is exempt from APA and RFA requirements.