Conventional start, Real Stars, period separator, 57 years in.
Four of the largest NPR populations in my game (two starting NPRs' homeworlds, the homeworld of an NPR generated early on by a starting NPR but still unknown to me, Raider homeworld) are currently being terraformed by their owners to remove all hydrosphere. The 1st NPR has a 4.7b population capacity homeworld and currently has by far the lowest hydrosphere of 3.7%, and after reviewing my save backups, I've been able to determine that the 2nd NPR's homeworld population peaked at around 3.9b before they started removing their water, which would correspond to the growth penalty threshold of their 11.7b capacity homeworld. The planet's hydro was at 17% when I assualted it, however I haven't been able to locate any terraforming ships or installations.
I'm aware of the "NPR terraforming now works correctly." bit in 2.6.0 changelogs, but I haven't been able to locate any reports or mentions of this bug in particular, so I'm still bringing it to your attention.