"He's not serious?" he(Harry) muttered to Percy.
"Must be," said Percy, frowning at Dumbledore. "It's odd, because he usually gives us a reason why we're not allowed to go somewhere -- the forest's full of dangerous beasts, everyone knows that. I do think he might have told us prefects, at least."
As I understand the bold sentence above, Percy do think Dumbledore possibly had told prefects, but for some reason, Percy were not aware of it. Is my understanding correct?