Pulling Threads

"Awful things happen to wizards who meddle with time, Harry."
Fifteen years after they first discovered that books were factual records of events in other worlds, the International Society of Fans figured out how change the endings. After months of debate, they assassinated Kreacher to save Sirius's life. Then they hurried on to the next series, sure that they had secured a happier ending.
Unfortunately, they were wrong.
Unforeseen consequences fall out in ever wider ripples. Now Hogwarts is in ruins, and Voldemort rules openly. Even the muggles begin to notice as he turns covetous eyes to the rest of the world . . .
And all that stands in his way are the ragged, fugitive remnants of the Order of the Pheonix, and, of course, the DA.