On a lot of levels, this is the core of the entire story, the inciting incident, the generation of the myth.

Harry Potters mother dying in the attempt to save his life, then Harry survivjg the unlockable killing curse.

The text states that the protection is created by Lily's love and the sacrifice of her life for Harry, which I don't disagree with, but there are a lot of mechanics behind the magical "internal consistency" of the Harry Potter universe and Lily's sacrifice as related through Harrys dementor-induced memories do not "fit."

She's wandless... what human is capable of that, this is old magic, deep magic. Unexplained magic...

So what do I think happened? I think the adults around Harry are dancing around a slightly tainted branch of magic that facilitated Lily's selfless sacrifice to save her son.(Alliteration?)

What were her last words?

"Not Harry, not Harry, please not Harry."

"Not Harry, please no, take me, kill me instead---"

"Have mercy..."

And what this screams to me is Lily has outlined the terms of a contract writ in blood, Voldemort instantly signs it and then instantly violates the terms and conditions, dooming his direct efforts for 7 books to come.

Essentially all the things told to Harry are true in essence, but it also fits better on Harrys final survival than require more convoluted protections activating or lapsing based on weakly supported guesses..

Specifically the idea that Voldemort taking his blood restarted the conventional Lily sacrifice shield that lapsed when Harry turned 17?

And that's how he reflected the killing curse in the forest?

That... doesn't work as described.

If he lost it when he came of age, and no one recast the protection, why would essentially cloning a body using another's DNA with some of your sequences CRISPred ineith no recast or corollary additonal sacrifice. How could it come back?

Expand on the idea or poke holes in it.