for mobile, I believe after either umbrella comes out or when the last two new fighters come out in 2022, the latter makes the most sense to me since the new story will be able to add in these 4 new characters as a challenge in story mode for the first time and that will add a lot more variety to the new story gameplay-wise
Two story options: 1. Current: More story for the present day, Skullgirl Marie crisis. Story modes for Annie, Umbrella, and (as StarUrania mentions) the other two (probably Marie and Black Dahlia). Could have "what-if" non-canon endings (e.g. "destroy" the Skull Heart or make a wish). I'm hoping for one unified, definitive, storyline. Like, what happens to everyone, who defeats Marie, and how tall of a building does Beowulf suplex Vitale Medici off of? You know, the usual questions. 2. Future: A Skullgirl appears every 7 years. So a true sequel, the REAL Skullgirls 2, should happen seven years in the future in their timeline. So if you want true continuation, look there! Would be weird though. Can you imagine a 20 year old Peacock?