When the Jews rejected their own Messiah, Paul tells us that God shifted his redemptive focus from them to the Gentiles. Granted, there have been quite a number of Jews who have put faith in Jesus Christ through the ages since he was rejected by the bulk of them, but by and large they are hardened to even the consideration of him. The banner over them as a people has been Ichabod: the glory has departed. Does that mean that God has washed his hands of them? No, there are seven years of redemptive work yet to finish with them, and God ever true to his word, will not forget them nor stop short of his promise to them.
So when will the clutch be depressed and the stick shifted from Gentile gear to 70th week gear, and when will Jesus return for his bride? According to the scriptures, no one knows, and no one could ever know! Wait a minute, aren't there dependable signs that clearly mark this out? Not really, and that's why his return will always remain unexpected. We can gather that we are closer to that event, but Christians have thought the end was at the door since Jesus ascended to heaven, and yet the bridegroom delayed.
The one thing that does seem to be significant is the Temple. At the start of the 70 weeks, in the issuing of the decree to rebuild Jerusalem, the Temple was paramount. Jesus said he would rebuild the Temple in three days, meaning the Temple of his body (which has become the Gentile church). Shortly thereafter, the Temple in Jerusalem was destroyed. It seems sensible to me, that in shifting the redemptive focus from the Gentiles back to the Jews, the Temple in Jerusalem would be the central issue again.