They've been doing test fires with helium to clean the inside of the stellarator for the past few months. This news is because yesterday, with hydrogen, they ran a plasma at 80million degrees for 0.25 seconds. Still a few years away from the goal of 100 million degrees for 30 minutes, but it's a huge achievement. When that's working they'll start putting deuterium in and the fusion fun will begin, but not at a level that actually has a net energy output. That will only happen with tritium, but that won't ever be done in this particular stellerator (at least there aren't any plans to do it).