IMO, if these dupes have IBLs and you try to 301 the page then the negative just moves with them. Kinda' like when someone buys a domain and 301 redirects to another site to drain the PR out of it before discarding. Not the best strategy if you want to move back to where you were previously. How much value can these have if they are dupes? No reson to 301 it isn't worth the risk. You can always do that later after you have figured out the cause. IMO, you still don't know that until it turns around.

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