hello 500 above
As discussed before, the conditions for both the FAR25 and JAR 25 are for the failure of the critical operating engine at V1. 400 feet is a certification limit under these conditions. Earlier in this thread I've explained why I believe this does not prohibit the retraction of the flap in the case where all engines are operating. That is also why the AFM's do not refer to 400 feet in relation to flap retraction on an all engines operating take off.
I'm definitely not saying that no AFM exists which has this condition written in. I am, however, saying that the case of an engine failure after the flap retraction speed or even further up the climb, is not explicitly defined. Perhaps you could read a couple of the earlier posts regarding this to see if they make sense - if they don't, then post. You may be absolutely correct and I may have completely missed something.
cheers