In case you hadn't guessed from all the textual clues, Dumbledore is just a manifestation of time-traveling Ron Weasley.
I will never be intimidated into silence about Ronbledore. Wake up, sheeple. The evidence is already all there in the books. Did Cedric Diggory know too much about Ronbledore? Why is "Cho Chang" an anagram for "Weasley Time Prison"? Why does Parvati Patil keep referring to Ron as "Headmaster Time-Child" during the Yule Ball before she dissolves into a disembodied ball of gas? We're through the looking glass, here.
Also, time travel apparently reverses one's sexual orientation, which accounts for all the bisexuals on Torchwood.
ETA: As requested, the above link is to a piece on The Toast satirizing an interview with Rowling earlier this week, as covered by LemonadeLover.
Also, there is a Part 1! Thanks MyPrettyFloralBonnet!