Oooh, sounds awesome! Although, if you are planning to do post-event stuff with this, these is something I should note - this plot was actually originally conceived as a way to change canon-points, and that's still an option here.

Basically, at the end of it when the affected characters' time is returned to them, it won't be returned exactly right. Now, for most characters this will probably just mean something small and insignificant like 'they lost five minutes of time' and thus will still effectively be from the same canon-point. But if you are wanting to change canon-points, it's definitely possible for them to permently lose (or gain) some time to rework their canon-point. I'm not sure if this is what you might be planning, but if it is then this is something to consider.