The last major battle of My Hero Academia, Deku vs Shigaraki, has been given a time limit. Deku has five minutes to beat Shigaraki before he's too exhausted to fight. This should mean that the Final War Arc will be wrapping up soon, but it's far from over.
Kohei Horikoshi has wound the clock back on MHA's story to cover what's happening on the rest of the war's main fronts. It's likely that once the rest of the battles on these fronts have reached their conclusion, it will be time to cut back to Deku and Shigaraki. At the very least, this arc can't be properly concluded until the audience sees what happens in these battles.
What Major Battles Are Being Fought?
Currently, the story is focused on the battle at Central Hospital. On the villains' side, Spinner is leading Paranormal Liberation Front soldiers and Mutant Quirk Civilians in a raid on the hospital to free Kurogiri. Standing opposed to him are Heroes led by Present Mic, including Rock Lock, Tentacole, and Anima, as well as several law enforcement officers. As of Chapter 372, "Naked," Spinner and Present Mic have reached the villain and are trying to call out to Kurogiri and Shirakumo, respectively.
Another key front is the Gigantomachia Containment Facility in the Jaku Hospital ruins. Several villains are trying to breach the facility and free the behemoth, including the sludge villain and the PLF Executive who killed Midnight. They are being fended off by Heroes led by Mt. Lady, including Mudman, Emily, Rule, Grape Juice, Red Riot, and Pinky. The Class 1-A students notably have a personal stake in this fight due to their love of Midnight.
Himiko Toga is currently at the Okuto Island Aquarium fighting Uravity and Froppy. She has some High-End Nomus and Moonfish, who are currently being dealt with by Heroes like Gang Orca, his sidekicks, and Sirius. Toga and Uravity have each resolved to fight for what they believe in, despite the former's old desire to connect with the latter.
Dabi is currently at Kamino Ward Ground Zero with another large High-End Nomu. He's being dealt with by Shōto, Ingenium, and Endeavor's sidekicks, including Burnin, Onima, and Kido. It seemed like Shōto had beaten Dabi at first, but he has since regained consciousness, seriously injured Onima, and begun heading to Endeavor's location.
As for Endeavor, he and Hawks, aided by Tsukuyomi and Earphone Jack, are battling All For One at the ruins of the Gunga Mountain Villa. Meanwhile, Heroes like Kamui Woods, Shishido, Pixie-Bob, and Shemage are battling the surrounding villains. All For One has used Eri's Rewind Quirk to revert the state of his body, but it will soon revert him to nothing. Before that, however, he plans to reconvene with Shigaraki and free him from the trap the Heroes set up for him.
What Is the Importance of All These Fights?
Shigaraki is essentially a prisoner at UA High. The school building has been converted into a floating fortress, which is being maintained by several students and faculty members like Power Loader, Cementoss, Mei Hatsume, Creati, Chargebolt, and Comicman. Shigaraki is also having his Quirks suppressed by the team of Eraserhead, Phantom Thief, and Manual. This is to say nothing of him having to fight Best Jeanist, Mirko, the Big Three, and Deku; Dynamight is dead, but he'll presumably reenter the fight if Edgeshot can successfully resuscitate him. Mandalay is also there to relay messages between the team and the outside world; this doesn't hurt Shigaraki directly, but it does emphasize how alone he is in all of this. Again, this fight will probably be focused on again once several other matters are attended to.
Besides this, there are a few more miscellaneous fronts in this final war. Sugarman, Tailman, and Cellophane are fighting random villains at Takoba National Stadium. Fat Gum and Can't Stop Twinkling are fighting Kunieda and other villains still at the Troy parking lot. It's unclear what effect if any these battles will have on the larger-scale war.
Things are quite precarious on the Heroes' side of the conflict. One of their winning conditions was keeping the major villains separated. If they lose on either the Kurogiri, Dabi, Gigantomachia, or AFO front, it could create a domino effect where they all find their way back to each other. If the villains regroup, the Heroes will lose their biggest advantage against them.
In any case, MHA has at least five major fronts it needs to cover before it can return to UA. Once the results of these battles have all been squared away, then the story can return to Deku's climactic battle with Shigaraki. Some of these fronts might even have an adverse effect on the Shigaraki fight. It all depends on whether the Heroes on the scene can score decisive victories on all of these fronts.