They could, but my understanding is then it would count as a new airplane, with more training required for pilots to fly it. They were trying to pretend it was

They could, but my understanding is then it would count as a new airplane, with more training required for pilots to fly it. They were trying to pretend it was not a completely new airplane, so that pilots wouldn't need much new training to be certified to fly it. It is turning out to have been a pretty bad decision, even from a mercenary point of view.