The quote (I don't remember where exactly in AToJ it is):
But we must try to postpone the day of reckoning as long as possible, and try to arrange society so that it never comes.
I think it was past section 40 but before Part 3, so was in some of the more "applied political ethics" area of the text. But so what is this day of reckoning supposed to be? He later brings up the ressentiment of Nietzsche (I think), or at least conservative theories of destructive communist envy, but I doubt he would have viewed a Nietzschean or communist reckoning as morally expected in the event of a failure of the two principles of justice. Or maybe he meant that one of those reckonings, any of them, could be expected disjunctively? "If the two principles fail to secure and advance their place in history, then reckoning A or reckoning B or... will take place"?