The article points out he is eligible for parole after a third of the sentence, and that he'll receive credit for time already served. They even do the math for us - he'll be eligible for release in 8 years.
Leonard Peltier is still in prison. It's extraordinarily unlikely that Manning will ever be paroled; the U.S. Government holds grudges, as Greenwald's spouse has so recently seen.
uhm, the UK government is the government that detained Greenwald's partner, not the Feds