Season 3 of The Umbrella Academy is going to include a time travel heist much like Avengers: Endgame as the heroes battle to restore their timeline. The second season of Netflix's adaptation of The Umbrella Academy ended not with an apocalypse but certainly with a world-ending revelation for the Academy's six surviving members. They jump back to 2019 in the wake of JFK's assassination only to find that after meeting them in the past, Sir Reginald Hargreeves never started the Umbrella Academy, instead turning his superpowered adoptive children (including a not-dead Ben) into The Sparrow Academy.
The meddling with the timeline should, according to most established rules of movie and TV time travel, mean the Umbrella Academy cease to exist since they would never have been trained by Hargreeves and would never have ended up in the past, but this continuum clearly works differently. Interestingly, that now means that the Academy will be able to jump into the past from 2019 to potentially change the events that led to the alternate future they arrived in at the end of season 2. And given that everything they knew about their lives has been snapped away by the establishment of an entirely new timeline defined by the existence of The Sparrow Academy.
The result is that The Umbrella Academy's third season has the potential to take major leads from both Avengers: Endgame and Back To The Future in sending the lead characters back in time to fix the timeline and restore their own futures. And while seemingly just one of the Academy - Aidan Gallagher's Five - is capable of time travel as part of his powers, there is an opportunity teased in season 2 that would allow all six members time travel. Given that chance, which isn't as simple as The Commission giving them open access to their briefcases, the Academy should embark on a time heist to get their lives back.
Why The Umbrella Academy Timeline Changed
The end of season 2 of The Umbrella Academy subtly confirmed that Sir Reginald Hargreeves consciously changed the timeline after encountering the Academy in 1963. His greeting to his former adopted children suggested that he'd been waiting for them to turn up at some point and even that he'd made preparations for it. And ultimately, his decision to completely change his own future, by scrapping the idea of the Umbrella Academy and replacing it with the Sparrow Academy is a direct consequence of Luther, Diego, Vanya, Klaus, Allison, Ben, and Five meddling with his life.
In the end, the Academy didn't actually derail Hargreeves' plot to stop JFK's assassination, because that would have happened either way (thanks to the Majestic 12 or The Commission), but they interfered enough in his life to change things massively. The impression they left after their meeting at the Tiki Lounge was disastrous, considering how unimpressed Hargreeves already was with each member he'd already encountered. Having bested (and almost killed Diego), Hargreeves humiliates him, Klaus has an extremely odd seizure when Ben possesses him, Allison rumors Diego to punch himself in the face and Luther rips his shirt open. Hargreeves seems strangely unimpressed with Vanya's powers and only Five's teleporting raises an intrigued eyebrow. No wonder he saw them as failures. And since they are his creation, the only answer is to change how he molds his super-team, the second time around.
Almost more important is how Diego sabotages Sir Reginald's relationship with Grace. Compelled by his hero complex and convinced that his adoptive father is behind Kennedy's assassination, Diego shows Grace what he believes is irrefutable evidence convincing as much, completely changing her perception of "Reggie." Even though he's clearly a flawed character, he is not quite the murderer Diego sees him as, but what matters is that Grace now probably believes that too. And removing her from Hargreeves' life removes her positive influence on her, making him even more of an extremist in his measures and his control of the Academy, as suggested by the fact that they continue to wear their school uniforms even as adults. Without Grace softening him and with the looming fear of what his Academy could become without a firmer hand, he will become a firmer taskmaster and that leaves no room for the Umbrella Academy. But why are his changes allowed to stick?
Vanya Created The Umbrella Academy's Apocalypse Again
In the words of Diego "Vanya is the bomb. She will always be the bomb.” Though Vanya's hand in destroying the world in the 1963 alternate timeline was averted by Ben possessing her and calming her powers, Vanya still effectively brought about the end of the Umbrella Academy's world. She did so by single-handedly killing all of the Commission's field agents and putting the entire Commission - somewhat ironically - out of commission in the wake of The Handler's internal part-destruction of it. Sure, there's a new version of the organization led by the more mild-mannered Herb temporarily, but without their agents, the Commission cannot hope to be effective in their agenda to protect the space-time continuum.
It's now going to be the responsibility of the Umbrella Academy to be the de facto Commission for season 3 as they take over on the organization's goal of ensuring everything that is supposed to happen does happen. Given the fact that the Umbrella Academy exists in the first place, they were clearly a protected part of the timeline, particularly because they play such a key part in the apocalypse, which again is also supposed to happen. In a strange variation on the themes of the first and second seasons of The Umbrella Academy, it would appear that in attempting to restore their own timeline, the six will be acting in the best interests of the apocalypse.
How The Umbrella Academy Can Jump Back Through Time
Season 2 of The Umbrella Academy established during the climax of the battle on Sissy and Carl's farm that Five can now use his powers of time travel to more precisely wind the time dial to his will. After a pep talk by the 1963 Reginald Hargreeves, ironically, Five learns that greater focus and aiming lower by not trying to jump years is the key to controlling his powers. But that comes with the caveat that he won't be able to precisely jump back in time to either the 1960s again or to somewhere beyond 1989 to stop Hargreeves changing events in time. But he's not the only way season 2 hints at time travel being possible. Putting aside The Commission (because they are presumably still a mess under Herb and with no agents left), there's also a blink-and-you'll-miss-it nod to Sir Reginald Hargreeves own time-traveling invention: the Televator.
In the Umbrella Academy comics, the Televator allows Hargreeves to travel through both space and time and it plays a key part in "Dallas," the second comic book limited series from which the JFK Assassination story for the Netflix show was taken. The designs for the invention are spotted in 1963 when Grace breaks into Sir Reginald's secret room and uncovers his plans, including for what he has labeled "the next great mode of transportation." That means that if the Umbrella Academy can get their hands on the device, which presumably exists somewhere in the timeline beyond 1963, they can jump back in time to change everything back.
What matters next is when they jump back. They presumably can't just undo the events of 1963, because it's necessary for Five to meet Old Five on the Grassy Knoll to send him back to 2019 through the portal to protect his own future timeline. So the key time jump has to come after that and involve the Academy attempting to convince Hargreeves that they need to exist in place of the Sparrow Academy (no doubt with an added kicker of a third apocalypse somewhere along the line) as well as trying to mend his relationship with Grace so she can go on to be their Mom. If there's not an Enchantment Under The Sea Dance Easter egg in there, it will be a missed opportunity.
The Umbrella Academy Are Sort Of The Villains Now
The third season also throws up a totally new dynamic, because the Umbrella Academy are essentially going to be the villains, at least in the Sparrow Academy's eyes. Their plan, after all, will see them changing the timeline to wipe the Sparrows out of existence if they're to get their own happy endings. That will likely not be the Sparrows' idea of a good time and Sir Reginald will presumably also take some convincing, which may form an interesting sub-plot in season 3 as the entire Umbrella Academy has to adopt Diego's obsession with impressing his father for validation.
It's not simply a matter of the two Academies co-existing either. They cannot just sit comfortably in the new 2019 timeline because at least one of their reasons for returning has been wiped from the timeline. The whole point of Allison's heart-breaking decision to leave Raymond and come back to the future was that she had her daughter to worry about. If the Sparrow timeline is set in stone, Claire won't exist, so Allison could be the key to sending her siblings back in time, not least to protect the impact of Raymond's loss at the end of The Umbrella Academy's second season.