Umbrella Academy Season 3 left fans reeling after the revelation that Sir Reginald Hargreeves is the villain behind Hotel Obsidian and the siblings are in another timeline. Fortunately, Umbrella Academy Season 4 is set for 2024 and will wrap up the story of these siblings' journey. But one sibling, in particular, is in need of a more complex arc than the others.
Source:https://www.cbr.com/umbrella-academy-redeem-allison/