All the apostles taught from the old testament as they preached the new. Johns writings were never known to them.
But God was filling in the blanks.
Paul never read johns writings he went to glory before the ink meant the paper.
Peter, paul and the rest preached Christ crucified the missing link to there understanding of what the prophets were saying.
Hearing all the good news I'm sure they heard that the christ would return. I'm sure they were taught of the signs of his coming.
I'm sure that the details were all in their old testament scrolls. It just made more sense now.
70 ad was for sure terrifying with the temple destroyed and the horrific persecution taking place. One back then would say are these the end of days. Did we miss the Lords day. Then there might of been others that said "did not that prophet from nazareth speak of this?"
Before the regathering there had to be a scattering as the Lord declared. That's what 70ad was all about the further scattering the Lord talked about for Israel his people. Some say this was a punishment from God for the crucifixion of jesus. I say not so for two reasons. Jesus said " no man takes my life but I lay it down. And in revelation jesus returns to "the house of his friends.
The jews brought it on there selves by saying "may his blood be upon us and our children and our children children" a traditional oath of old. Some serious stuff.
Anyways I don't think they were confused by end time events. And I'm for sure they were real.

