..before Abrham, I am.
so, outside of time...
God told Moses, "I AM ("eHYeH) THAT I AM ("eHYeH] Say the the children of Israel, "I AM ("eHYeH) has sent me to you."
Exodus 3:14 KJV — And God said unto Moses, I AM THAT I AM: and he said, Thus shalt thou say unto the children of Israel, I AM ("eHYeH: uncompleted verb form of hayah) hath sent me unto you.
Biblical Hebrew had no past , present or future tense forms of its verbs. The temporal context of a verb was indicated by adverbs and context. Verbs were indicating whether an action or state was/is/will be already completed, or was in an on-going uncompleted state at the time indicated by the context.
When God said to say "I AM sent me," He used the progressive form of unspecified tense.
God gives His name as "I was being/I am being/I will be being." It is the Hebrew description that befits someone who is adapting to sequential events.
I would expect a Being who is unchanging and complete in a timeless now to use the
completed form, "I was/I Am/I will be" with some temporal adverb to fix the verb in the present.
If John wanted to use Greek Grammar to convey the concept that the same Person who was existing now incarnated as Jesus of Nazareth had also been existing before Abraham was born, what options did he have?
Even in English we use the present tense to talk about a past event in a manner that presents it as an unfolding in progress replay to the audience's mind. Before JeanLuc was born I am in the video shop and three balaclava-ed men with shotguns are coming in shouting to everyone to get down on the floor. Is it possible that Jesus was doing something similar here? He could tell this story to some of His saints in the millenium:
"Before Abraham was called I'm looking over the planet for some man to found a nation through which I will incarnate..."
He is simply describing the past in a vividly immediate way.
If this linguistic tool is being used, "I am existing before Abraham came into being" is simply Jesus describing the past using a syntax that to His listeners' minds presents the past in a vivid way as it was when it was in progress, just as I could say " I am running marathons before my son was born," meaning that I am running marathons now but I have been doing so since before my son was born.