Go outside and look up, is the Sun darkened? Wait until night, go back outside, is the Moon still giving off light, are the stars falling out of the sky? Is there a massive army of holy angels and male virgin saints and Jesus in the sky? Are all the filthy fornicators of every singly race in our generation mouning and crying because there is actually a God and he is the one they rejected? All these things will happen in a single generation and that generation won't pass until they all happen.
Matthew 24:29-34
29 Immediately after the tribulation of those days shall the sun be darkened, and the moon shall not give her light, and the stars shall fall from heaven, and the powers of the heavens shall be shaken:
30 And then shall appear the sign of the Son of man in heaven: and then shall all the tribes of the earth mourn, and they shall see the Son of man coming in the clouds of heaven with power and great glory.
31 And he shall send his angels with a great sound of a trumpet, and they shall gather together his elect from the four winds, from one end of heaven to the other.
32 Now learn a parable of the fig tree; When his branch is yet tender, and putteth forth leaves, ye know that summer is nigh:
33 So likewise ye, when ye shall see all these things, know that it is near, even at the doors.
34 Verily I say unto you, This generation shall not pass, till all these things be fulfilled.
I don't think you understand Preterism. This doctrine takes the word of God literally and it cannot be taken figuratively when it is speaking literally unless it doesn't fit when they are interpreting literally in which case it must be taken more as a guideline unless that also does not fit in which case you ignore it.
For example, "not one stone left on another, that shall not be thrown down" that can be taken literally for 70 AD, therefore you cannot look at this figuratively as believers are living stones, the church is the temple of God and when the rapture takes place those stones whose faith is resting on the doctrine of man, for example Preterism, will be thrown down.
You shall hear of wars and rumors of war. Practically speaking the people in Jerusalem heard of one war, not wars, and perhaps rumors associated with that war. So you can't take this literally therefore you must consider that Jesus was speaking more as a guideline. War, wars, its all about the same thing. And when they "hear" of these things it is not referring to radio or TV or the internet, no it means your neighbor is telling you this.
An even better example of this principle is "you shall be hated of all nations for my name's sake". Obviously that cannot possibly refer to 70 AD unless you understand that this was simply Jesus speaking in hyperbole. He didn't really mean "all nations" when He said "all nations" He meant the Roman Empire. It was an empire, so think of it as a conglomerate of a few nations.
Likewise this "gospel of the kingdom shall be preached in all the world for a witness to all the nations", again hyperbole. Obviously this never happened by 70 AD. No one took the gospel to China by that time. No one took the gospel to North or South America, or many other nations. Now you might ask "why"? We can see that indeed the gospel has gone to these places during the church age, but you see if the answer to the question "when" is 70 AD then you have to ignore all evidence to the contrary.
For example no one saw the abomination of desolation stand in the Holy place in 70 AD when they fled. So the rule is simple, it doesn't fit the answer, so just ignore it. When they say you must believe every word of the Bible they mean "every word that supports our theory". They don't mean verses that debunk it, those you are to ignore.
Now test yourself to see if you got it
For then shall be great tribulation, such as was not since the beginning of the world to this time, no, nor ever shall be.
So if this is referring to 70 AD what do you do with the Holocaust, and other Genocides? Do you A. take this literally? or B. see this as hyperbole or C. Ignore it because it debunks the theory?
The answer is C.