At best, this is all speculation. 7-8 years is the time before Chelsea Manning becomes eligible for parole. Whether or not she is actually released will depend on a number of factors, including the political climate at the time. We'll only really find out around 2021.

Finally, and this is something I touched on in my first comment, even 7 years in a federal prison is nothing to sneeze at. A non-trivial amount of time spent on federal probation after release isn't exactly going to be a cakewalk, either. And this is all on top of the time already spent in the military justice system, including almost a year of solitary confinement. Basically, I'm just asking that we don't downplay what must be an awful experience simply because our justice system has wiggle room.