I'll retract my previous statement and just say what you're trying to argue has ZERO meaning. Why? because theories are theories, and consciousness is not proven to be physical, and even if it was, it doesn't matter in this context.

There are key components that of which make up anyone's experience as a human that don't rely on purely brain matter. You being present in time right at this moment, with all your sensations, making decisions is enough to make your experience valid. I'm honestly too fucking tired to do a in-depth rundown but imagine this. If you made an exact copy of someone and put them in the exact same environment, would their thoughts follow in the same exact order sequentially? Or would they be highly variable? That deviation in itself would prove a mere copy of atoms does not equate to you. You see the thing is, everything you do, every decision you make is all apart of what makes you, you. What i'm getting at is your mental state is directly tied to your physical state as time passes through you.

No I'm not the same person, nobody is.. but my continued conscious experience is still alive. Don't conflate the two. When I say pretend, I mean the copied brain or whatever apparatus thinks it's me but it will never truly be me.

Sadly that would only be a clone, meaning you will still die the same way with someone else taking your place who merely pretends to be you.