Time is not so simple when God the Father is involved. With Jesus, God is very much involved. God’s speech brings things into existence, even before humans would think those things exist. If God speaks Jesus into existence by saying ‘I will beget a son’ it is the same as saying ‘I have a son’ because God’s word is so powerful. The spirit of this Son therefore came into existence long before the historical event of the conception of Jesus. I do not know God well enough - the Father’s power and transcendence of time - to know exactly about this. Clearly for the Father to only beget one son in all time it must be something that took place when God formed that decision and spoke it into history. I believe the testimony of Jesus that it was before Abraham was born and before the creation of the world. I interpret John 1 as John by the Holy Spirit saying it happened before anything was created - the spirit of Christ came into existence before anything created was created - and was involved in all God did since then, including in Creation.
