Update
This was confirmed to be a mistake by Niantic Support a short time after the issue was discovered. both Kyurem fusions have also been removed, with Niantic claiming that they will grant compensation for the loss.
Original Post
In terms of the future of Pokemon Go, few Pokemon are quite as anticipated as Kyurem's formes when fused with Zekrom and Reshiram; Kyurem Black and Kyurem White, respectively. They have massive potential, and both could be very powerful... though Kyurem Black is generally very much expected to be the superior of the two. Regardless, the current expectation is that we won't see these two behemoths until Go Tour: Unova, which will likely be in 2025. Well, it seems that Niantic thought that waiting wasn't the way that things should go, as Kyurem Black and Kyurem White are now available via Go Battle League!
Reported by MaarkusB on The Silph Road, the two advanced formes of Kyurem are now available via the Go Battle League. However, this is a huge new addition to the game, and it's entirely unannounced as of right now, so it's likely that one of two things is happening right now:
Niantic Made a Mistake
Niantic has a track-record for making mistakes when they make changes to Pokemon Go, giving us precedent for issues like adding moves to Pokemon that they can't learn in the main series. As of right now, it seems pretty likely that this was an issue of someone at Niantic not enabling the correct version of Kyurem, resulting in these monsters now walking the Pokemon Go world in all of their power and glory.
This is a Not-Yet-Announced Release
Kyurem is set to return as our Five Star raid boss on December 16th, and recent event announcements have mysteriously not included it in their raid boss list (though the current Mega Evolutions are also missing, admittedly). This could mean that Niantic intended this as an unexpected surprise, and we can expect to see a big announcement drop within the next 24 hours.
Regardless of the situation, it seems that Black Kyurem and White Kyurem are here. However, we will not be updating the database with information on them until we figure out what's actually happening. While unlikely, it is possible that Niantic may apologize for the issue in the coming days and swap out all existing Black/White Kyurem for their basic forme to make this right. Either way, we should know what exactly is going on soon!
