Well, this puts my lesson in temporal mechanics in a whole new light.
The whole premise of alternate timelines/realities is Newtons third law, for every action there is an equal and opposite reaction. This applies equally to all our decisions, little or big, each creates a quantum event, splitting time for each option. Now, for our little choices, the ripples in the 'water' disperse quickly and those separate existences meld back together without a fuss. De ja vu and the Mandela effect are symptoms of this melding of quantum states happening, the former more often for little things, the latter more for large things. Now theoretically it should be possible to use magiq to essentially preform surgery on these quantum states and meld our timeline into the one we create by opening the Book in the past while keeping Basecamp and all our connections alive, thereby creating a new quantum state, born of the two old ones.