Certainly, WHEN the demons cried out, He was in human form as the Son.
However, remember when Michael was contending for the body of Moses? Whom did He call to rebuke? Was it not the total authority of the very creator - the Lord?
When Jehovah appeared with two other visitor before Abraham (Genesis 18-19) He is not referred to as a Son but the very God - yet in appearance of a human.
It isn't that I disagree with the eternity aspects, rather, I take the Scriptures do present that there was a specific place in the human aspect of understanding time, that the very Jehovah, the LORD, out of Love for the creation, set aside the eternal glory, "being found as a human" performed all that the prophets spoke concerning the first advent, and then was again exalted by the Father. Therefore, the eternal sonship, is a question in which the eternal son began at the time of human conception, but the eternal Christ was as recorded of Melchizedek (imo, another illustration to the Christ) - without birth, death, and worthy of all praise.
I have already responded to part of this.
I will add another aspect already somewhat discussed (if I recall) in the thread.
John opens with the Logos. The spoken word of God. That all creation was through the spoken word, and that word became flesh.
Remember the angel coming to Mary, and explaining the power of the most high overshadowing her?
See, it isn't that Christ had a beginning for God cannot die. Rather the son had a beginning as a human. The very Creator took upon himself human flesh. In that submission, He took upon the roll of Son to the Father.
In the Revelation, it displays the Christ in the glorified form, and equal with God.
4they will see His face, and His name [will be] on their foreheads. 5And there will no longer be [any] night; and they will not have need of the light of a lamp nor the light of the sun, because the Lord God will illumine them; and they will reign forever and ever.
Did not Christ state, "I am the light...." ?