There is no such thing as replacement theology, you can't replace something that never existed. The flesh descendants of Israel have never been and never will be the children of God.
Rom 9:6 Not as though the word of God hath taken none effect. For they are not all Israel, which are of Israel:
Rom 9:7 Neither, because they are the seed of Abraham, are they all children: but, In Isaac shall thy seed be called.
Rom 9:8 That is, They which are the children of the flesh, these are not the children of God: but the children of the promise are counted for the seed.
Quite right when speaking of "replacement" theology according to dispensensationalism - the true replacement theology is replacing the physical nation with the spirtual nation which is what the scripture stated would happen.
The promises to Abraham were intended and indeed were for Christ who created the nation of priests:
Gal 3:16 Now the promises were spoken to Abraham and to his seed. He does not say, “And to seeds,” as
referring to many, but
rather to one, “And to your seed,” that is, Christ.
1 Pet 2:9 But you are A CHOSEN RACE, A royal PRIESTHOOD,
A HOLY NATION, A PEOPLE FOR
God’s OWN POSSESSION, so that you may proclaim the excellencies of Him who has called you out of darkness into His marvelous light;
The children of the flesh were cast out in the 1st century AD:
Gal 4:30 Nevertheless what saith the scripture?
Cast out the bondwoman and her son: for the son of the bondwoman shall not be heir with the son of the freewoman.
Gal 4:31 So then, brethren, we are not children of the bondwoman, but of the free.
According to dispensationalism and amill "theologies" they are to be cast back in, but they again contradict scripture as usual
Luke 13:28 There shall be there the weeping and the gnashing of the teeth, when ye may see Abraham, and Isaac, and Jacob, and all the prophets, in the reign of God,
and yourselves being cast out without.