Fanboys complaining about continuity problems in their favorite mass media entertainment have always been an issue. Over 2000 years ago, Horace wrote in the Ars poetica

...indignor quandoque bonus dormitat Homerus

presumably complaining about Pylaemenes being killed in combat by Meneleaos but then showing up many books later to witness the death of his son. (From this passage, we get the phrase "Even Homer nods.") Christian scripture and religious writing are full of retcons reconciling the Gospels with contradictory passages in the Jewish bible, but perhaps the first secular retcon comes from Alexander Pope's Essay on Criticism:

I know there are, to whose presumptuous Thoughts
Those Freer Beauties, ev'n in Them, seem Faults:
Some Figures monstrous and mis-shap'd appear,
Consider'd singly, or beheld too near,
Which, but proportion'd to their Light, or Place,
Due Distance reconciles to Form and Grace.
A prudent Chief not always must display
His Pow'rs in equal Ranks, and fair Array,
But with th' Occasion and the Place comply,
Conceal his Force, nay seem sometimes to Fly.
Those oft are Stratagems which Errors seem,
Nor is it Homer Nods, but We that Dream.