Yeah, I get that. I was thinking, say if the time travel book changed things in PG, then maybe Molly wouldn't be the WL maybe Murphy wouldn't be dead.
There were a few story lines set in motion in that book and some foreshadowing of things to come. Maybe if Murphy didn't lose her position in SI, she wouldn't have lost her life to Rudy. Maybe, knowing what we know of HWWBs, Harry could help Mab free Maeve of the infection.
Otherwise, if the book stays the same, we will get answers on the loose ends. My guess is that this is the way the book will go. But I would like to see a book where Harry is fighting the timeline that has happened, not showing how what we know to have happen how it happened.