The librem 13 v1 coreboot image is ready and you should be able to give it a try by doing as @mladen suggested (the iomem=relaxed boot option or boot into the old 4.7 kernel if you still have it on your boot menu) then run the script.
The one that gets installed when you do sudo apt-get install purism-librem-coreboot-updater is I think outdated, but you’d need to install it so it can bring all the dependencies with it.
The reason that this has not been publicly announced yet is because we need to go through a round of beta testing first, just to be extra sure there are no issues. I was also caught up on testing NVMe support which seems to be working fine apart from one user (who is also having issues on the original BIOS, but I don’t know if it’s a problem with his NVMe drive or it’s something that can be fixed in coreboot).
The librem 15 v2 coreboot port is not yet done, as it was a higher priority to get the latest hardware working so they can be shipped with coreboot preloaded on them. But I’ve learned so much in doing these ports that I don’t expect the L15v2 port to take very long (probably a day or two).