It is a position you hold until a belief system provides sufficient evidence for you to form and hold a belief.

Gnostic atheism is a specific form which nobody actually holds to, which says that there positively is no god and this is known to be a fact. Any reasonable person would admit you can’t know this. And so virtually all atheists are agnostic atheists.

Being an agnostic atheist does not mean you are “on the fence” or “undecided” or “accepting of all beliefs equally.” It means you are intellectually honest that you cannot prove the non-existence of a god any more than you can prove there isn’t a planet in the universe where it rains lemonade. But until you have a firm reason to believe that some god exists, you’re going to proceed as if they don’t, because that’s the conclusion, however perpetually provisional, that best matches the evidence.