The specific issue in question has nothing to do with high altitude Ice Crystal Icing (which the GEnx has also had issues with).
Rather, this particular issue is related to the more conventional icing threat (i.e. super cooled droplets) that forms ice on the fan blades at low power. Based on what is currently known, it only applies to one 'version' of the GEnx-1B engine. No known impact on the GEnx-2B (747-8) or the earlier versions of the -1B on the 787.