Retcons, canon snapshots, canon drift over years. How a Franchise expresses 'canon as of 2028 was X, canon as of 2032 is Y'.
Why this matters
Retcons, canon snapshots, canon drift over years. How does a Franchise say “the canon as of 2028 was X, the canon as of 2032 is Y”?
Without explicit version-control semantics, retcons either erase history (bad for Atlas-style reference uses) or accumulate as parallel claims (confusing to readers). Related to LoreLine persistence (G-025) and fork mechanics (B-001) — when a snapshot diverges enough, when does it become a fork?