Just put my dev HA onto 0.89b3 and can confirm that it does break this CC.
It seems that it is the changes mentioned by @claytonjn a few posts up.
@robmarkcole - any chance of an update to it? From reading the breaking change it does seem quite a major rewrite though?
If i understand correctly (I am an IT geek and enterprise infrastructure engineer, not a programmer), the breaking change means that a custom component has to be ‘all in’ or not. So this one will take control of the whole Hue integration, not just the sensors?