The last chapter of Punkzilla is Jamie's first letter to P, the one that set his journey in motion; it's dated December 2, 2007. Jamie writes to tell P that he's gone AWOL from Buckner and is now living in Portland. At first he says he doesn't want to give P his address, but he really wants P to write back, so he writes the address on the inside of the envelope.
This is the letter to which P responds in Chapter 4, telling Jamie he's dying and including enough money for the Greyhound bus ticket. In the last paragraph, Jamie wishes P and Jorge a merry Christmas and asks if they still have their cat, Carlos.
In going full circle like this—in visiting the moment that launches the whole book we've just read—we're reminded just how big a loss P's death presents for Jamie. Sad face.