[omgitsmatt]

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I loved the book, but I'm still trying to figure out how Dumbledore's portrait knew they switched the date for Harry's departure. I spent the whole book thinking there was a traitor in the Order, and it turns out Snape's source is Dumbledore!?



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Snape's source was Mundungus Fletcher. We see that when we go through Snape's memories.

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Hmm...I read that as Dumbledore (well, his portrait) coming up with the idea for the seven decoys and telling Snape to plant that idea with Mundungus. I didn't draw from that that Mundungus was feeding information to Snape all along.

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Well the idea is that the portraits aren't really sentient, they just repeat catchphrases. But apparently Dumbledore's can do more than that (actually, it also looks like Sirius' ancestor could do the same). I'd say that Dumbledore, when he was planning everything that was going to go down, fed his portrait the information that it would need to carry on in his absence, so to speak.