Jimmy and his classmates had largely completed their courses, and what followed was a new training module added after 9/11, focusing on surveillance and counterterrorism.
After 9/11, the FBI shifted its primary focus to counterterrorism, transferring a significant amount of resources to this area. The FBI began to adopt the CIA's methods of acting proactively, gathering intelligence early on, and using the vast database of fingerprints and criminal records in FBI laboratories, as well as immigration files, to conduct surveillance on suspected terrorists, tracking their whereabouts and activities to prevent attacks from happening.
A vivid analogy is that before 9/11, the FBI was like a catcher in a baseball game, waiting for the pitcher to throw the ball and then responding. The CIA, on the other hand, was like the pitcher, taking the initiative and acting on gathered information.