In their final rejection of the Messiah, God has cut them off from His promises and has given the fulfillment of His promises to those who repent and believe. Galatians deals with this very extensively. The New Covenant has come. The Old has passed away. The unconditional Covenant made with Abraham is being fulfilled daily when sinners repent and turn to God in faith.
There are some serious questions you must ask yourself. I once believed as you did. I was steeped in "rightly dividing the word." My theme song was, "My hope is built on nothing less, than Scofield's notes and references." But God in His grace and mercy opened my eyes. And I pray He does the same for you. You make God to be a bigamist (or worse yet a fornicator) if you hold to your beliefs - married to a wife Israel and have another bride the church (or worse yet, a mistress). You may not state that openly but your belief carried to it's logical conclusion states that.
I implore you to search the Scriptures without your precious dispensational outline and let God speak to your heart. You can come to only one conclusion when you read Galatians, and Romans and the Gospels. God is finished dealing with natural Israel and now focuses His love and attention on his Birde, the church. Why is that so hard for you dispensationalists to see? Why do you keep harping back to Old Testament conditional promises? Why can't you see that God is finished dealing with a specific nation and now deals with all nations without discrimination? Why can't you let the New Testament interpret the Old Testament? Why do you continue to love the shadow when the substance has come? Why do you continue to not give Christ His proper place as Husband to His Bride, the Church.? Why do you continue to hold preference to national Israel over the New Testament chruch, God's true chosen ones?
How about Heb.8:8-13, Rom.11:1,11,26-27, Rev 7:4-8 (where the 144,000 are sealed, 12,000 each from the 12 tribes of Israel