The narrator suggests that Ove knew all along what he had to do, but says that all people are "time optimists" and operate under the incorrect assumption that they will have enough time to do and say things to people.
This idea of "time optimism" is in direct opposition to memory and grief: when people find their time optimism is faulty and they don't actually have time, it ends in grief.
When Ove comes down the stairs, he notices that the house smells like toast, which it hasn't smelled like since Sonja died. He accuses Mirsad of making toast and notices that Mirsad made coffee and fed the cat as well. Ove tells Mirsad that he's going to take a walk with the cat. Mirsad asks if he can come, and Ove agrees, after looking at Mirsad like he's crazy.
Mirsad makes himself at home in Ove's house, which also forces Ove to change or abandon his morning rituals. It's all very strange for Ove, but it also reminds him of Sonja, which suggests this will turn out okay.
When they get outside, Jimmy runs up to them and greets them. He's in a tracksuit and is panting. He tells Ove that he's starting to exercise and wants to join Ove on his walk. Mirsad briefly explains to Jimmy that he's not getting along with Amel and is staying with Ove. Ove stops Jimmy from asking Mirsad uncomfortable questions.
Jimmy is changing up his own routine by beginning to exercise, as well as interrupting Ove's routine. Ove's protection of Mirsad suggests that he understands the value in taking some time to grieve privately for one's lost family.
Jimmy asks Ove if he has heard that the council is picking Rune up today. He explains that Anita has been trying for two years to get more help for Rune and now the investigation is closed. Ove refuses to accept this and says that Sonja would've heard about it if it were true. Jimmy says that Anita asked him to not say anything to Sonja, since she and Ove had so many troubles of their own.
Finally it comes out that Anita wasn't honest with her best friend, in an attempt to protect Sonja from more grief. We see that the council does take time to make decisions, but the time has simply already passed. This shows that Ove was himself a "time optimist," as he's already been doing things to stop the council.
Ove is silent and continues his inspection, but grows noticeably angrier. Mirsad asks Ove if he's okay, and Ove turns and asks Jimmy to confirm Anita's reasons for not wanting to tell Sonja. Ove thinks that Sonja would've been heartbroken to find out. He mumbles that he thought he had more time to help, and then strides off to Anita and Rune's house. He bangs on the door and Anita opens it. Ove steps in without being invited and asks for the paperwork. The narrator says that Anita hadn't seen Ove so angry since a possible Saab-Volvo merger in 1977.
Ove knows that Sonja valued her community above all else, and knowing that her community hadn't allowed her to help would've been heartbreaking. This finally spurs Ove to action. Remember that though Ove finds fights with white shirts exhausting, fighting is exhilarating for him, and this particular fight has the added suspense of a time limit.