Hey, I heard from our device team that the Compute Module 3 should be available on the latest beta version, that is on our staging or experimental site at https://dashboard.resinstaging.io (that is resinOS v2.0.0-beta13.rev3 for the Raspberry Pi 3).
It’s in testing phase, would be great to hear any feedback! 
The v2.0.0 production release is not too far, and from then it will be available on the regular resin.io site too.
It looks like there are other people experimenting with the Compute Module as well ( @simonkemper and @curcuz for sure), here’s some more discussion as well.