I was also not aware they had had officially shelved a COVENANT sequel, only the Blomkamp project. If that is the latest news, I refuse to accept it just yet. No way they're going to leave that story unfinished. I'm fairly confident there will be a sequel at some point, either by Scott himself or someone else.
Seriously if Scott has a brain he's done with Alien - your wanting for a series - movie that goes back to the near beginning of the narrative, Scott could of boarded eggs in Alien but it wouldn't of worked-out very-well for Cameron's teeming sequel. No more!