Not quite. The Word was the eternal Son, but the hypostatic union did not exist until the Incarnation. And it exists to this year and will for eternity.
However, what I am saying is that the "hypostatic union" that came into being at the incarnation did not change the nature of God. The nature of God remained unchanged. The hypostatic union was simply the ADDITION of something else (human) without any change of the God nature itself brought together in harmonious union in ONE PERSON without confusion or mixing of the two.
The hypostatic union is not God, if it were God, then God CHANGED at the incarnation into something previously non-existent. Thus a NEW GOD.
The hypostatic union is not God but only the union or bringing together in ONE PERSON what is God and what is man.
From that point forward the immutable nature of God joined with human nature coexists in one Person.
Just as there are three co-existing Persons in the ONE GOD without confusion of Persons, there are two co-existing natures in the ONE PERSON of Christ without confusion of natures.
Although the nature of God includes both communicable and incommunicable attributes, it is the non-communicable attributes alone that distinguish God from all other beings and make God to be God, which without, he would not longer be God.
Likewise, the nature of man includes shared attributes with other beings, but there are some attributes alone that distinguish man from all other beings and make man to be man, which without, he would no longer be man.
In the PERSON of Christ both the incommunicable attributes of God and man existed without confusion - coexisting together.
His human body in heaven is not omnipresent, but located in heaven at the right hand of the Father.
Only his divinity remains omnipresent just as demonstrated in John 3:13 when his deity was present in heaven but his body located on earth before Nicodemus.
And no man hath ascended up to heaven, but he that came down from heaven, even the Son of man which is in heaven. - Jn. 3:13
Moreover, just as between the Persons of the Godhead, there is a heirarchy of position or authority, so is there between these two natures in Christ. His deity is in the position of authority as it is His deity that determines what manifestations of God are revealed through his humanity and what extent of knowledge and wisdom that is obtained by the man Jesus. As a man, he grew in both wisdom and knowledge, but deity is immutably omniscient and cannot "grow" in either. As a man, he did not know the time of his own coming, but in his deity He knows all things including that time. The divine nature stands in the position of authority over his human nature as the finite is in submission to the infinite. This is a WILLING and FREE submission as it is between the different Persons of the Godhead. Both natures act in harmony but not without distinct seats of consciousness with one in a position of authority over the other. The divine nature determines the extent of knowledge possessed by human consciousness. The man Jesus is not conscious of the time of his own coming, but the divine Jesus knows all.
Multi-seats of consciousness exists between the THREE PERSONS in the ONE GOD. It also exists within man as man's consciousness is controlled by two different laws indwelling the one and same person (Rom. 7:15-25). In fallen man these two seats of consciousness are in conflict. However, in the one Person of Christ these two natures are not in conflict as the human nature is in a willing and free subjection to the divine and thus exist together in perfect inner harmony and peace.