When Alister used the Memory Recovery (Purple) talent throughout the entire World of Fantasia, he recovered the memories of everyone from the previous timeline.
He didn't recover the memories of those from the other timelines since they were quite inconsistent. Like for example, he had offended the heroes in the other timelines but in the previous timeline, he was the heroes' leader.
The previous timeline was his perfect run since he had let the entire world know about the hero party's heroic deeds. The entire world was literally changed by their hero party for the better, especially the human race.
Alister and the hero party had rooted the corruption in Blue Star and they even killed a lot of nobles due to that. They had also made connections with those from other races so it could be said that the previous timeline was Alister's best simulation timeline yet.
