I bought my butterscotch Appaloosa frame on March 8, 2016. Will told me it was one of the last ones (if not the last one, maybe only the last one in 55cm size) they had.
It is a great bike. I just rode it to work today in freezing weather 7.5 miles in.
Side note: I really wish someone would start putting together a list of production numbers, years, and colors the bikes came in. I have a small hunch Rivendell bikes will be very collectible years from now still, in the same way Serottas, Ibises, or Fat Chances are collectible now.
Michael