Even without the Painkiller news, I'm surprised by this. Especially given that the show was just brought into the Arrowverse proper. That and I would've figured another of the long running shows like Flash would've ended after Supergirl. But for Black Lightning to be next...I wonder if they have plans, if this was always in the cards, or something else.
Hope it ends on a high note, but I'm sure it will. When it comes to the DCCW shows, Black Lightning, for my money, has been the most consistent as far as its quality, which I can't say for Arrow, Flash, Supergirl, or even Legends.