Care to describe/define what you think is a "person" vs what is a human, so we don't all jump to conclusions by relying on how just such human-replacement/substitute terms have been used in history? Also, why should "person-rights" replace "human-rights" as our standard for treatment of others?
I do not believe that everything that is genetically human must automatically be afforded person rights. The simplest way to think about it is that since rights are not absolute but a social convention, it stands to reason that only members of the society are automatically accorded "membership" rights. Humans outside that society do not have them, but can acquire them. Conversely, humans inside a society can lose their membership rights under certain circumstances, e.g. gross misconduct.
Believe it or not, this is how human societies have functioned in practice since times immemorial. The entire system of jurisprudence is a study in how membership rights are reassigned based on level of misconduct. Criminals generally drop form "gold membership" to something else. Immigrants get naturalized and boosted to full "gold membership". If you follow human history you will see this happening innumerable times in all forms and guises.
Simultaneously, there is the general illusion that somehow "pan-human rights" are preserved and accorded based on religious ideas of equal creation etc, which was later modified to genetically based rights once people learnt a bit more biology. My approach is more sociological than genetic.
From this pragmatic perspective, the issue of abortion is really an issue as to when the genetically human material is ready to enter the society as a full member, very much like an immigrant is naturalized under certain circumstances. Thus my desire to understand when that would be appropriate is naturally emanating from this very pragmatic/mechanistic sociological view.
Now, I understand that there are no "natural" inhibitives for all sorts of violence to be perpetrated by abuse of the above society-based view. It is not my job to provide such because I believe in personal choice and freedom of association. If a bunch of fascists/zealots want to come kill me because I am no member of their clique/cult, then it is their choice to do so, as it is mine to blow them away.