Per discussion: https://en.wikipedia.org/wiki/User_talk:GreenC_bot#Bad_webcitation_link_replacement

Sometimes archive URLs are soft-404s. But changing the archive URL in IABot won't modify existing archives on-wiki.

Feature idea is tell the bot to change all archives from one to another. For example, a check-box underneath the archive-url entry box that says "Modify all URLs on-wiki". It would only change the archive URL with the same snapshot date eg. any occurrence of source https://web.archive.org/web/20140813072851/<url> would change to target https://web.archive.org/web/20101019072851/<url> .. if the source snapshot is not 20140813072851 then it would not be modified.

This would also be useful as an API call because I am getting lists of archive URL soft-404s from Citation bot - triggering IABot to run with the updated snapshot date would be very useful.