Hi, sorry for the late reply …
I do maintain a beaglebone black image at http://people.canonical.com/~ogra/snappy/all-snaps/ since we dropped it as an official reference platform.
While the core 16 image uses my own armhf re-build of the linux-generic kernel in the ubuntu archive (called linux-generic-bbb), in core18 there is an officially maintained build of this kernel snap (confusingly called “pc-kernel” in the store). I am working on getting daily builds for the core18 bbb image up and running ATM.
So with core18 we have about 90% of the support back. While I am still maintaining the gadget and model, the rootfs and kernel are fully supported and get security and bugfix updates automatically.
I have also been talking with drew fustini and jason kridner at embeddedworld this year and we might be able to arrange that beaglebone.org takes over the gadget maintenance eventually, so you can have actual official images from them.
Meanwhile if you want to try core18 on beagle hardware (before the bbb image is ready), I made an experimental pocketbeagle image available pretty recently at:
(check the README for info)
I’ll update this thread once there is more info about further “officiality”