On a terraforming-related note, isn't Planetform said to have not actually finished a project yet, despite their many many years of existence? Mostly due to how long it takes and all.
So even if they couldn't get to the planet in Tau-31, all the various organisms (such as alien organisms) and whatnot are still changing the atmospheric composition and such. It just wouldn't be going as fast as before, when they were introducing massive amounts of other gases and the like.