...not plan, decree, plan, the final point was plan, decree, God. As the plan or decree is God. That's what John is saying. But yes, it is circular, and that's the effect, or art of the poetic form that he's using.
But, understand that each usage does not have to have an entirely different meaning, just a different emphasis or effect than the adjacent use i.e. just not used in the exact same way that it was before...
...but, the meaning is understood, Jesus was not an afterthought, it was designed from the beginning, and all this was God's intent as that is who and what God is, wisdom, love and sovereign.
It can be said in a variety of ways, and is repetitive, but that's for the sake of emphasis. But, appreciate when John said this, in the 1st century, so to us, what I'm stating is obvious and sounds mundane, but at that time, it was extremely revelatory, and profound.
I'm just saying, reading it in a hyper-literal fashion does not do justice to the thought of John or what he's trying to convey. It actually does the opposite, you end up with an absurd and irresolvable conclusion, i.e. god-man, triunity, redundancy in the Godhead, an inefficacious atonement, etc...