A useful distinction
A control or rule can change while an old test note remains in a folder. Without a version or date, that note may be mistaken for evidence about the current prototype. A short change log gives the sequence context.
Put it into practice
Record the date, changed behaviour and reason. Link test observations to that version and preserve unresolved questions. Avoid marking an issue fixed merely because the source was edited; repeat the relevant behaviour check and record what the updated prototype actually did.