The absence from GE1 (→FE>EE) of the dot prolonging b
1 is undoubtedly an oversight on the part of the engraver.
The authenticity of the variant written into FEJ is doubtless due to the known origin of that copy. This allows us to approach with more trust the variant visible in GET, which is an extended version of the idea noted down in FEJ. The analysis of the melodic structure of that bar makes us even consider the variant from GET a better version than the one in FEJ. The outline of the printed version 
shows us that Chopin operates here with a variant of the motif of the second main theme of the Nocturne (bars 10-11); the outline of the supplemented version: 
reveals a smartly done earlier return to the melody led in thirds, so characteristic for that motif.
Compare the passage in the sources »
category imprint: Differences between sources
issues: Annotations in teaching copies, Inaccuracies in GE, GE revisions, Annotations in FEJ, Annotations in GET
notation: Pitch