It is certain that there were a few stages of the introduction's shaping, which is revealed by the differences between the existing sources and analysis of the corrections visible in JC. Lack of autographs precludes a strict reconstruction of all changes, yet it is possible to recreate some of their crucial elements:
♦ in the previous, based on [AI] sources – JC and EF – not all bass notes are doubled in the bottom octave; what is more, the sources are not compatible in this respect:
JC 
EF 
In JC, in the places marked with asterisks, there are traces of erased dotted minims B
, B, and G. It means that it was only in the stage of corrections that the rhythm 
in bars 1-3 was introduced and the bass note at the transition between bars 3 and 4 was changed from G to B. The notation, probably simplified and inaccurate, of those, and maybe also other changes in [AI], turned out to be not entirely comprehensible for the copyists. The corrections, imposed on the short cut – as in JC – notation of the octaves resulted in the already mentioned discrepancies. In the entire fragment, we give the octaves in the L.H. which consistently appear in PE and do not raise any doubts, neither source nor stylistic.
♦ in the later stage of changes – in [A] (→PE) – Chopin introduced further improvements in bars 3 and 8.
Compare the passage in the sources »
category imprint: Differences between sources; Corrections & alterations
notation: Pitch