Well I usually don't know what kind of clearance I'm gonna give until I speak
Yes, as BrATCO pointed out they do exist. We also use CFMU's CHMI but, albeit you could look so many hours ahead, you need to know that isn't it, no one can predict the future. When looking at which sector configurations we will play out tactically, we analyze traffic with our flow unit and we almost never look further than 3 hours, as what we get tends to be unrealistic (unless it is one of those days when things play out like the computer predicted...which is, well, T.B.H. never).
In a way is like taking photos of waves in the ocean. Next time you look it has already changed.