Overbreed isn't dropping today, Breed & Bond is. No exact time figured, just sometime before I go to bed. So, within the next 12 hours since this answer is submitted.

Though if one really wanted to, they could imagine Breed & Bond is a spin-off of Overbreed. It wasn't intentionally written to be part of the same continuity, but I have conceived a rather roundabout set of mental gymnastics that makes it work. There are some continuity conflicts between Breed & Bond and Overbreed, but they're not too hard to overlook - just need enough time between Overbreed's story and Breed & Bond's story for all the kids conceived in the former's story to be born.

If you think about it too hard, it starts to bring up questions about parental ethics, since Overbreed ends with DVa, Pharah, and Symmetra all pregnant. But then, Breed & Bond's story explicitly establishes that Pharah and Symmetra knock up prostitutes and have impregnated several of the Overwatch cast before the events of the video. It's not likely these ladies are an integral part of all their childrens' lives (but I mean if you want to headcanon that I won't stop you), so parental ethics are kinda already out the window and are best not to think about.