As DC Comics prepares to welcome longtime Marvel mainstay Brian Michael Bendis to its ranks as the writer of its flagship Action Comics and Superman titles, the publisher's solicitations for May 2018 include an unexpected trade paperback collection that may hint at the shape of Bendis' plans for the Man of Steel. Superman: Zero Hour collects twelve issues tying in with 1994's Zero Hour event, which saw a newly-villainous Hal Jordan try to remake all of time and space in his image.
This trade stands out because it doesn't seem to connect to any established publishing priority -- it's not collecting a current series, it's not a collection of Zero Hour itself, and DC does not seem to be offering similar collections for other heroes (though Batman's tie-ins might merit one). That would suggest there's another reason to publish this collection now, and the most likely would be a connection to Bendis' relaunch.
So what's in these issues? In 1994, there were four ongoing Superman series, Action Comics, Adventures of Superman, Superman, and Superman: Man of Steel. There were also Steel and Superboy, featuring the ongoing adventures of popular heroes from the Reign of Supermen story arc that returned Kal-El to life.
Superman: Zero Hour collects two issues of each, with the first, a "numbered" issue, taking place during Zero Hour and featuring some alteration to the timestream, and the other, a "zero" issue, offering a new take or wrinkle on the hero's origin story. In the "numbered" issues, Superman meets Jor-El and Lara from a Krypton that never exploded; a Ma and Pa Kent who never raised him; a hero of Metropolis called Alpha Centurion, and his beautiful wife Lois Lane; and a whole bunch of Batmen.
Superboy encounters his pre-Crisis counterpart, and Steel… fights some techno-baddies, I guess.
But the #0 issues, the origin stories, may hold the more direct clues about Bendis' plans. While it does not seem there will be a hard reboot on the level of New 52 or Rebirth, DC is giving the writer room to build his own take on Superman from the ground up. The ongoing Superman series will get a new number #1, and before that Bendis will re-introduce the hero with a miniseries titled Man of Steel -- just as John Byrne did for the post-Crisis Superman in 1986. Byrne's series rewrote all of the rules, and the new mini is clearly a nod to that.