From a Kickstarter update post:
External casing modification
We decided to change the case size due to manufacturing challenges. A few of our components were larger than expected in the manufacturing model and needed a stronger internal mechanical case to secure their performance. Some components have also increased in size due to cost.
Currently our water heater is set at 95C = 203F. Higher temperature is possible. We will conduct more testing with the manufacture unit to make sure higher temperatures are consistent and accurate when above 205F.
The milk container is part of the machine. It was marked optional because it is not required to be there when brewing coffee that doesn’t have milk. In addition, the milk container can be taken out to wash and or separately put into your refrigerator.
Cocoa powder/Sugar powder container
While redesigning the syrup dispenser, with further research and technical investigations, we realized the humidity difference in each country may cause solidification in the powder container. So we are considering to replace the powder (cocoa and crystalized sugars) container with cocoa syrup and white/brown sugar syrup for our first version of Arist.