Stefan Achatz wrote last month in this support request, which is getting picked up today, that he's stepping back from the project. He is working on Roccat Skeltr support but "this will be the last device I'm doing, this projects ends here." The Roccat Skeltr is a RGB gaming keyboard.
He didn't elaborate if he's just tired of working on this open-source project over the years, whether his relationship with Roccat has deteriorated, or what factors went into this decision. Great job though to Stefan for his work on Roccat Linux support over the years and hopefully other open-source developers will decide to pick up where he's leaving off.