There seems to be a difference between change and replacement. Sperm and egg unite, and are changed into a new organism. While the sperm and egg perish in being united, it seems that they do not simply perish, replaced by the new organism. Rather, they turn into the new organism in some sense. It is this "in some sense" that is puzzling here—what does it mean? It seems to mean more than just that the sperm and egg have a causal role in producing the new organism—that would be to reduce material causes to efficient causes, and would be unsatisfactory. If an artist created a sculpture and happened to cease to exist just as the sculpture was completed, we wouldn't say that the artist turned into the sculpture.
A traditional solution to the puzzle is to suppose that matter survives substantial change. The matter of the sperm and egg loses its old forms, and takes on a new form, that of the new organism. But the artist does not turn into the statue, because the statue is not made of the artist's matter. Now, on my preferred view of matter (and my reading of Metaphysics Z), matter does not survive substantial change.
So it seems that there is a good argument against my view of matter: if matter does not survive change, then one cannot distinguish change and replacement.
But I have a response. If there is in fact no difference between change and replacement, then the above is no objection to my view of matter. Suppose then there is a difference between change and replacement. Then we will want to say that in transsubstantiation the bread and wine are not replaced by, but changed into, the body and blood of our Savior. But the matter of bread and wine do not survive transsubstantiation. Hence it cannot be the case that the only way to distinguish between change and replacement is through the persistence of matter.