I would add just one thing; the Apostle Paul's last days speak of apostacy, not revival.
"This know also, that in the last days perilous times shall come. For men shall be lovers of their own selves, covetous, boasters, proud, blasphemers, disobedient to parents, unthankful, unholy...having a form of godliness, but denying the power thereof: from such turn away" (2 Tim. 3:1,2,5).
For the time will come when they will not endure sound doctrine! But after their own lust shall they heap to themselves teachers having itching ears; and they shall turn away their ears from the truth and shall be turned unto fables." (2 Tim. 4:3,4).
the god of this world is working overtime to snare those who refuse to see the truth. Spiritual discernment is critical now.
One of my speculations, hunches is
that there will be great suffering
then a great revival
and that just maybe
God will harvest folks at the peak of that great revival.
I do believe He is looking to harvest as many as He can.