Star Trek: Everything We NOW Know About The 25th Century

Thanks to Star Trek: Discovery's fourth season episode The Examples, we know that the Q Continuum ceased contact with the Federation by around 2590. Though there is as yet no explanation as to why (this is perhaps something that Starfleet Academy may explore), this, when combined with John de Lancie's cameo in The Last Generation, means the Q were active in the interim. 

Q emphatically states that the infamous trial goes on, though now the focus of said trial has moved from Jean-Luc Picard to his son, Jack Crusher. It's possible that this was sequel baiting in the hopes of a Star Trek: Legacy spin-off, but it also connects to the wider universe. 

In 2401, Jack Crusher meets Q, who informs him that there is much to do still. Though at present, we have no way of knowing just how old our Jack lives to be, he can't be the last Federation representative to see a Q. He is (allegedly) in his early 20s by this point, which would mean he would be pushing 120, at least, by the dawn of the 26th Century. 

Admiral Leonard McCoy was at least 137 by the time he died (though we hope he was older and that Data didn't just push him out of an airlock), asking Jack to stick around until 2590 seems like a bit of an ask. It feels, then, like a sure bet to say that Q Continuum were active in the 25th Century, perhaps with Jack alone in that century, but far more likely with several members of Starfleet.

After all, our favourite Q spent time with Captains Picard, Sisko, and Janeway at roughly the same time. There was that run-in with Captain Pike as well, but that's all very hush-hush and swept under the wedding bells.