[Dynasty]

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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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Same here.

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I think you misread it.

It seems to me that Snape is consulting the portrait Dumbledore (pg. 688). Snape got the information "-from the source we discussed" (pg. 4) when he informs Voldemort about the date of Harry's depature from Privet Drive.

I think Snape was concerned about whether he could inform Voldemort about the actual date Hary was leaving. Telling the truth may have put Harry's life in too much jeopardy. The portrait Dumbledore is emphasizing the need to remain in Voldemort's confidence. So, it suggests Snape must report the accurate date to Voldemort.

It's not clear who came up with the idea of the decoys. It sounds like something which has been discussed before. The portrait Dumbledore seems to have concluded that Voldemort must be told the truth and decoys used to give Harry a chance to escape.

Remember, Mundungus Fletcher was in Azkaban at the end of Book 6. Presumably, he escaped during the mass breakout between books which also liberated Lucious Malfoy. It's not hard to see him playing both sides. That's in his nature.