I purchased this plant as Hoya merrillii around five years ago, and finally after all this time have found out its true identity!  I knew that although similar to merrillii, it did not match any online photos that I had seen of that species.  I have always  loved the plant, because it has some of the nicest leaves and the best form of any of the Hoyas that I grow.  Here are a couple of photos of the flowers just beginning to open on Hoya Pottsii Sp. Chiang Mai with more to follow in the coming days.