Timescaler here. Although we haven't done any official announcements w.r.t. clustering, our plan is for this to be open source, like the single-node version.
We wouldn't do this if we didn't believe we could make a business out of it. That said, we are at a pretty early stage at this moment and are looking at many different options. As you may know, and if you've been following the discussions around business models for open-source projects, there are many approaches as well as challenges. All I can say is that we have been following the discussions and we are drawing lessons from past failures and successes.
1. https://news.ycombinator.com/item?id=12649414