It's not up to me to be an authority on these matters, but I would like to share with you a possibility and see what you think.
I am thinking that what Jesus said applied to his day alone. It was a prophecy that came true!
The generation that rejected Jesus and condemned him to death did see the end. Jerusalem was destroyed in 70CE which was well within the timeframe that Jesus specified.
I think this makes sense. If this is the true understanding of the scripture, it is another reason for confidence and faith in our Lord and in the bible itself. It was a prophecy that came true! Simple!
I remember going from door to door and explaining to people that it was impossible for Armageddon not to be here by the 21st century, based on the teaching that 'this generation' referred to by Jesus in MATT 24:34 referred to anyone who was alive in 1914. I explained that someone from this generation must still be alive when the end comes. I still remember a gentleman once asking me, "What will you do if this doesn't happen?" I replied, "It will happen!" It just did not compute to me that what I had been taught could be wrong.
But of course we are now in the 21st century and so the fact is, what I was taught was wrong - which is not surprising after all that I've learned recently.
Interestingly, when the teaching changed in the mid 1990s I wasn't upset at all since I had always felt that the reasoning was rather thin. Nonetheless I believed whatever I was told.
The latest understanding of 'the generation' revolves around supposed overlapping
generations which does not make any sense whatsoever. Many can see this flaw in timing,
but not so many can see another major flaw in this reasoning.
The Watchtower's understanding teaches that when Jesus spoke of 'this generation' he was referring to his followers. This is NOT TRUE! EVERY REFERENCE that Jesus made while on earth using this term - 'this generation' - refers to the wicked in his day.
The Watchtower actually admits this fact about every other reference to the term 'this generation', acknowledging that this is referring to the wicked generation of Jesus' day , but .... they say that in MATT 24:34, Jesus was, on this one occasion, talking about his disciples. Their reasoning is that Jesus addressed his disciples at the start of his speech in Matthew 24 and thus the disciples knew that he was addressing them. THIS REASONING IS UNSOUND.
The scriptural proof of this is in LUKE 17:22-25. Ironically, this scriptural passage is actually referred to in the very Watchtower discussing the new understanding!
LUKE 17:22 shows clearly that Jesus was addressing his disciples. It says, "Then he said to the disciples:....." Jesus goes on to explain to them a number of things and while still addressing them he says in verse 25, "First, however, he (the Son of man) must undergo many sufferings and be rejected by this generation." Now surely Jesus was not inferring that his disciples were going to reject him? Of course not! So what is the difference between this passage and Matthew 24:34? Jesus was addressing his disciples in both passages. It's obvious that 'this generation' refers to the wicked.
Every time Jesus used the term, 'this generation' or 'this wicked generation' he was talking about the same people - those who wilfully rejected the Messiah. This generation is NOT talking about the righteous, it is referring to the WICKED!
So it doesn't even matter about overlapping generations. The basic teaching is flawed from the start and totally out of harmony with the rest of the scriptures.