In A one can see that Chopin initially wrote 
to mark the time signature on both staves. Moreover, the eventually left 6/8 reveal (also on both staves) minor crossings-out, which seem to be digits preceding the digits 6, although it is difficult to guess what their meaning could be. Anyways, it is an example of Chopin's hesitation, since the time signature in FCI, which was written earlier, is 6/8, like the final version.
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category imprint: Corrections & alterations; Source & stylistic information
issues: Changes of metre, Corrections in A, Chopin's hesitations, Deletions in A
notation: Rhythm