FE has a cautionary before b3 in bar 322. It must be a mistake – the accidental should have been placed at the pitch of a3. The error was corrected both in GE and EE, both also added an analogous in bar 326.
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category imprint: Differences between sources
issues: EE revisions, Errors in FE, GE revisions, Cautionary accidentals
notation: Pitch