RetCon

Retroactive continuity (Retcon) is a literary device in fiction whereby facts and events established through the narrative are adjusted, ignored, supplemented, or contradicted by a subsequently published work that recontextualizes or breaks continuity with the former.[2] https://en.wikipedia.org/wiki/Retroactive_continuity

There are various motivations for applying retroactive continuity, including:

To accommodate desired aspects of sequels or derivative works which would otherwise be ruled out.
To respond to negative fan reception of previous stories.
To correct and overcome errors or problems identified in the prior work since its publication.
To change or clarify how the prior work should be interpreted.
To match a prior work to the prevailing political narrative of a new author.
To match reality, when assumptions or projections of the future are later proven wrong.

Bill Seitz