In the sources, the time signature is 3/2. It is Chopin's mistake (the correct time signature is 6/4), perhaps related to the change of notation – Chopin started writing the Prelude with half the rhythmic values, which is evidenced by the reduced number of beams (one of the beams was crossed out) in the 1st accompaniment figure and by the dotted crotchets constituting the 1st R.H. chord (which was crossed out). The initial time signature was carefully blacked out, hence its interpretation is uncertain; however, it was most probably 6/8.
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category imprint: Editorial revisions; Corrections & alterations; Source & stylistic information
issues: Corrections in A, Errors resulting from corrections, Rhythmic errors, Deletions in A
notation: Rhythm