Practically nothing. With all of the attention that eschatology enjoys within protestant Christianity, many suppose that the Catholic Church has taught about this topic at length. But they would be wrong. Really wrong.
According to this Catholic Answers tract:
In the 1940s the Holy Office judged that premillennialism “cannot safely be taught”
The source is not cited (and the author is not credited). Not even the date is cited - only the decade (uncommonly sloppy scholarship for Catholic Answers, even in a tract). Which “Holy Office?” There are many. There is no such thing as THE Holy Office apart from the Pope himself (more uncommonly sloppy scholarship, unless the tract actually means to suggest that this was taught by a Pope). Something can be taught by the Holy See, or the Vatican, but THE Holy Office belongs to the successor of St. Peter alone - it is the Office of the Bishop of Rome.
I thus believe that it came from a minor Vatican Office that most people (and even Google, AFAICT) have never heard of. To my knowledge, this comprises the ENTIRE body of official Church teaching on the whole pre/mid/post trib, pre/post/amil topics. The Church simply has simply not taught about these things (probably because they aren’t part of the Deposit of Faith, which is the ONLY thing the Church can officially define). I have made this assertion in several previous threads, and nobody has offered any more definitive teaching.
Most Catholics that I know have absolutely no interest in end-times theology. It bores me to my core, but that’s probably because I don’t think that humanity has come even close to fulfilling God’s calling - I think we have THOUSANDS of years left, and it interests me about as much as the sun eventually dying - it will happen (and whatever is alive on earth will die), but it is irrelevant to me. If it was to happen tomorrow, it would matter A LOT, but if it happens a hundred-thousand years from now, I can’t get really excited.
FWIW, I am opening a new thread to discuss the tract I mentioned. I will probably not have the opportunity to link to it before my opportunity to modify my post here expires, but you can easily search for it.