Should an answer be rewritten completely if new external info becomes available?

Question

My question was prompted by this answer where the rules were unclear at the time of answering. The complete answer was now replaced with recent info from errata. The question wasn't ever changed in a way that changes what is asked.

There is guidance on updating old answers e.g. here and here.

The guidance seems to be that answers should be improved and wrong information should be removed.

In the present case I would however say that the info is not really wrong.

What is the right course of action in this case?

• Complete rewrite (as was done)?

• Create a new separate answer?

• Add the new info but retain some or most of the original answer?

• something else?

Answer 1

What I have done in the past is to update the top of the answer with the updated information, and then left the rest as “but before this change, this is how things worked,” for historical curiosity and/or for the sake of those who upvoted the answer on the basis of that description.

As an example, my answer to “When using a reach weapon, which squares around me can I attack?” in Pathfinder 1e.

Another approach is to edit the question itself to limit it to a particular timeframe, and possibly create a new question and link to it for the updated version. This is fairly clear and clean, but it would need to be a situation in which the before and after both warranted their own question—which is pretty unusual.

The last approach—which isn’t always an option, e.g. if your answer has been accepted—is to simply delete your answer. I don’t think there’s a lot of need for this, even when you can, though.