@rene Not if the target doesn't have an answer, but if the duplicate doesn't have an answer. That's when the user is redirected if there's only one target.
@rene Thanks, that makes a great starting point. How would I now filter this to only include those posts that were edited by a human user (positive user ID, or null user ID that isn't named "URL Rewriter Bot") after the ClosedDate?
I think this can be simplified by looking at the last active date. Automatic edits don't update the last active date (which is why those edits don't bump posts).
Never mind, scratch my last statement. I'm finding a few examples where the last active date was after the closure date but no human edit was made later (I don't know why). It looks like one must check the user IDs/names as per my message before that.
Found out why. Seems like this answer was updated in May 2012, then was moved to the target in 2015, which is why the last active date for the merge stub is the former.
But yeah, it seems we can't use last active date since it also includes answer updates. I totally forgot about deleted answers and answers that were merged into other questions. My first solution would only look at the question, which is what I was looking for.
@rene Seems buggy, as it's including negative user IDs (and so has the same result as the initial version of your prior query that did no such exclusion).
It's taking into account the automatic insert duplicate link edits immediately after closure, it seems.