The missing 
in GE seems to be an oversight of the engraver of GE1. However, performing this highly spectacular passage in dynamics is quite an uncommon effect, so that one can ponder whether the mark was not put in FE by mistake, e.g. instead of in bar 256, in which it was then added. Therefore, it would be an example of unfinished proofreading. (Cf. bar 248, in which a purely virtuoso element – scale in an interval of sixth – is dynamically distinguished between in bar 244 and leggierissimo in bar 250).
Compare the passage in the sources »
category imprint: Differences between sources
issues: Errors in GE
notation: Verbal indications