There may be other ways to handle this--I make no claims
this is the best. This is just what I'd prefer to encounter
if personally asked to unconsider a node.
Notify an editor, if one's around (or use the chatterbox), and wait with your
consideration vote to see if the editor needs it to
unconsider--unconsideration needs a certain number of keep
votes or a certain number of edit votes, and the post might
be lacking one of the right kind of vote to unconsider it.
If you get no response to your message, and the problem
hasn't been dealt with in about 5 minutes, the editor
probably isn't there.
If no editor is around, vote keep and message the editors
as a group. With only two keep votes deletion won't happen.
If you explain the reason in your message ("221876 was
thought to be a duplicate of 221901, but in fact it
isn't") the editor will spend less time verifying
and be able to unconsider more quickly.
