No Reformed, amillennial or postmillennial Christian that I know of believes that they're replacing the Jews in God's eschatology.
We can say that repeatedly, until we're blue in the face, and they will not hear it.
The notion that God breaks covenant is the biggest obstacle I see with replacement theology.
Likewise, none of us are saying God breaks his covenant.
From my NT reading yesterday:
Is this blessing then only for the circumcised, or also for the uncircumcised? For we say that faith was counted to Abraham as righteousness. How then was it counted to him? Was it before or after he had been circumcised? It was not after, but before he was circumcised. He received the sign of circumcision as a seal of the righteousness that he had by faith while he was still uncircumcised. The purpose was to make him the father of all who believe without being circumcised, so that righteousness would be counted to them as well, and to make him the father of the circumcised who are not merely circumcised but who also walk in the footsteps of the faith that our father Abraham had before he was circumcised.
further down
If that is the case, and God has somehow “dispensed” with Israel, then I find the teaching in grave error.
Israel "kata sarka" needs, like everyone else, to come to Christ, lest they be lost.
but that does not place anyone else in line for something God explicitly and exclusively promised to His “Chosen” people.
Read the epistle to the Hebrews, on what Abraham was looking for, as the fulfilment of God's promise to him.
We can say that repeatedly, until we're blue in the face, and they will not hear it.
Thinking about it, the only Christians groups I know of that place eschatology at the same doctrinal level as Christology are modern (as opposed to historic) pre-tribulational dispensationalists.