And I did. And I had.

[BFRZ]

"In that tremendous flash of freedom, on my way to do the Thing for the first time, sanctioned by almighty Harry, I receded, faded back into the scenery of my own dark self, while the other me crouched and growled. I would do It at last, do what I had been created to do.
And I did.

Chapter 17
And I had. So long ago, yet the memory still pulsed in me."

Кто-нибудь может объяснить, почему это утверждение сменило tense при повторе?