The fullness of Gentiles and the lifting of the blindness happens all of the time, day by day.
This is incorrect. What does "the fulness of the Gentiles" actually mean? Once you understand that you will also understand when "all Israel shall be saved". The Greek word "pleroma" (translated as "fulness") is explained thus:
Strong's Concordance
pléróma: fullness, a filling up
Original Word: πλήρωμα, ατος, τό
Part of Speech: Noun, Neuter
Transliteration: pléróma
Phonetic Spelling: (play'-ro-mah)
Definition: fullness, a filling up
Usage: (a) a fill, fullness; full complement; supply, patch, supplement, (b) fullness, filling, fulfillment, completion.
In the context of Romans 11:25 "full complement" or "completion" is the most appropriate application. And what this means is that God has already planned for a FINITE NUMBER of Gentiles to be grafted into the "good olive tree" of Israel (believing Jews). So the Church now consists primarily of Gentile believers and a minority of Jews.
When the total number of Gentiles is complete, the Church will be raptured.
After that God will resume His direct dealings with Israel, and after the Second Coming of Christ "all Israel shall be saved". Now "all Israel" cannot mean every Jews since many Jews will not believe on Christ even after He appears physically on earth again. Only 1/3rd of all Jewry worldwide will be saved at that time:
And it shall come to pass, that in all the land, saith the LORD, two parts therein shall be cut off and die; but the third shall be left therein. And I will bring the third part through the fire, and will refine them as silver is refined, and will try them as gold is tried: they shall call on my name, and I will hear them: I will say, It is my people: and they shall say, The LORD is my God. (Zech 13:8,9)
But "all Israel" can certainly mean "all the tribes of Israel", and we see a microcosm of this in the salvation and rapture of the 144,000 redeemed Jews (who prefigure "all Israel" on earth). It is noteworthy that the 12 tribes are never presented in the same order each time they are listed. In Revelation 7 this is the order:
Judah, Reuben, Gad, Asher, Naphtali, Manasseh, Simeon, Levi, Issachar, Zebulun, Joseph (Ephraim),
Benjamin (and Dan is missing).
The order in the OT (Gen 35:22-26) is as follows:
The sons of Leah:
Reuben, Simeon, Levi, Judah, Issachar, Zebulun
The sons of Rachel:
Joseph, Benjamin
The sons of Bilhah (Rachel's handmaid, Jacob's concubine):
Dan, Naphtali
The sons of Zilpah (Leah's handmaid, Jacob's concubine):
Gad, Asher
However, Jacob blessed them in the following order perhaps by age (Gen 49):
Reuben, Simeon, Levi, Judah, Zebulun, Issachar, Dan, Gad, Asher, Naphtali, Joseph, Benjamin.
But when we turn to Ezekiel 48, we see how they are placed in the land of "Greater Israel" (from north to south):
Dan, Asher, Naphtali, Manasseh, Reuben, Judah, Levi, Benjamin, Simeon, Issachar, Zebulun, Gad.
In any event, God is not finished with the twelve tribes of Israel. He also has twelve thrones for the twelve apostles of the Lamb who will sit on them and judge the twelve tribes of Israel. We do not know why they will need to be "judged".