Was Jonathan right when he said, "Don't you think there might be other flocks, other Fletchers, that need an instructor more than this one, that's on its way towards the light?" Why or why not?

The novella Jonathan Livingston Seagull by Richard Bach tells the story of a seagull who is dissatisfied with his normal everyday life of squabbling over food. Instead, he decides to apply himself to perfecting the art of flying. Because he does not conform, he is expelled from the flock. He encounters two gulls who invite him to a higher plane of existence. Through the wise gull Chiang, he learns of new possibilities of freedom and speed while flying. Ultimately, however, Jonathan becomes dissatisfied with his life on this higher plane and determines to return to Earth to teach other gulls what he has learned. Fletcher is Jonathan's first student.
After Jonathan has spent time teaching Fletcher and other students, at the end of the book, he says to Fletcher, "Don't you think that there might be other flocks, other Fletchers, that need an instructor more than this one, that's on its way towards the light?" In saying this, Jonathan is telling Fletcher that, in his opinion, Fletcher doesn't need his help anymore. He thinks that in this flock, Fletcher can take over the instruction of the other gulls while Jonathan moves on to help other flocks.
To decide whether Jonathan is right in saying this, consider what happens after Jonathan disappears. As Jonathan is bidding him farewell, Fletcher is upset. However, as soon as Jonathan is gone, Fletcher immediately begins to confidently train other gulls. From this, we can discern that Jonathan was right, and it is safe for him to leave the trainees in Fletcher's care.