The preterist has a problem. For example.
Luke 21:34,35
34 “Be careful, or your hearts will be weighed down with carousing, drunkenness and the anxieties of life, and that day will close on you suddenly like a trap. 35 For it will come on all those who live on the face of the whole earth. Be always on the watch, and pray that you may be able to escape all that is about to happen, and that you may be able to stand before the Son of Man.”
If it was all 'said and done' in 70, then one has to explain the "whole Earth" part, and the 'standing before the Son of Man'. All done?
The 'dual fulfiller' like Watchtower has a problem. Matthew 24:21 shows that there can be no "next time".
21 For then there will be great distress, unequaled from the beginning of the world until now—and never to be equaled again.
Them what believe at all have a problem. Matthew 24:1 “Truly I tell you, not one stone here will be left on another; every one will be thrown down.”
There's still lot's of stones on top of other stones there in Jerusalem. In fact, there's a whole tower itact. You can visit.
And, Jesus said Luke 21:31
" 31 so [also] ye, when ye see these things to be done, know ye, that the kingdom of God is nigh."
Perhaps any believer can explain how it was that the kingdom of God 'came' in 70CE. I know that the Romans came. But kingdom of God???
The link I placed above is the only document I've read that answers all the questions for me.