Paul's example was to make it clear that people must act from the heart, not by birth, correct, but it has absolutely zero to do with Isrtael supplanting the Church.
You can try until you are blue in the face, but Jeremiah was quite clear.
You've said this a couple times. However, this is my argument. Israel doesn't supplant the church. The church is the fulfillment of the Israel prophecies, not the other way around.