According to forum #2677 , the answer I received from asking for clarification about images marked "Do not distribute" seemed vague (do_not_distribute happens to be a real tag here on e621 with almost 100 images tagged as such).
From what I could implicitly gather from the replies, any DND image is granted the same consideration of pay material, and that any pay image that is older than two years can be posted to e621. So it is therefore okay to post Do Not Distribute imagery older than 2 years.
Of course this was not explicitly stated, but implied. Please confirm? Since that time I posted in the old thread, e621 underwent some management changes, and I don't want to get into any trouble with the rules here before I start posting ancient pre-2005 era non-commercial furry porn with "Do Not Distribute" on it.
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