The question was discussed in the thread “My Theory about the Flood”. For the sake of accessibility to interested readers I develop my argument with pleasure in the follow:
First of all let me remark that about 362,000 humans in God’s Image are created each day around the world presently, that is, in “a separate moment in time from humanity’s initial creation”. So to this extent my interpretation regarding Genesis 9:6 is nothing bizarre.
Presumably you are astonished because I claim that Genesis 9:6 refers to the creation of Image Bearers the same way as God created the first ones (“Adam and Eve”). i.e.: by endowing human-like animals with capability to freely love Him.
Notice however that Genesis 6:2-4 explicitly refers to human beings called “sons of God” the same way as Adam is called “son of God” (Luke 3:38): This means that the “sons of God” in Genesis 6:2-4 were created the same way as Adam was created but in a separate later moment.
Gordon Wenham [Word Biblical Commentary I, Genesis 1-15, Word books: Dallas, 1987] following Claus Westermann claims:
Genesis 9:3-7 explain “why human life is specially protected, but animal life is not”, and proclaim “the inviolability of human life” that follows from “the unique right of God over life and death”: “Every single violation of this limit, be it based on national, racial or ideological grounds is here condemned” [p. 251]. Indeed the remark in Genesis 9:3 concerning food indicates a degree of distinction between humanity and the animal kingdom that was lacking in the vegetarian diet of Genesis 1:29 [p. 263-264]; and in Genesis 9:5-7 appears for the first time the prohibition of killing any creature belonging to humanity because mankind is made in the image of God.
One may wonder why this distinction and this prohibition were omitted in Genesis 1:26-29, as the “image of God” is mentioned for the first time. And even more astonishing is that the prohibition was omitted in Genesis 4:15, where to protect Cain God does not proclaim that he shares human blood and belongs to mankind but “put a mark on Cain so that no one who found him would kill him.” A reasonable explanation for such an “omission” in divinely inspired Scripture is that a sharp distinction between human and animal life would not fit with the ontological status of pre-diluvian Creation; such a distinction is appropriate only once all human-like animals on the earth were transformed into human persons. Since this allegedly happened after the Flood, only then (Genesis 9:5-7) God categorically proclaims that the right to life, foundation of the personal rights, is defined by the belonging to humanity. And here we meet to some extent the interpretation of Hendel, R. S.: The Flood narrative with its introductory pericope of the “sons of God” ends ordering “the human cosmos” [Of Demigods and the Deluge: Toward an Interpretation of Genesis 6:1-4, Journal of Biblical Literature, Vol. 106, No. 1 (1987), pp. 13-26, and References therein]. The ordering happens mainly by means of an explicit formulation of the foundation of rights and law.
Please let me know whether I have answered your question or you desire further clarifications.