This update caused my MBP to go into a reboot loop. A black error kept coming up asking me to reboot.
Tutorial to restore from last APFS snapshot:
Apple software updates creating APFS snapshots on macOS High Sierra | Der Flounder
I had the same problem. It tuned out that the update to High Sierra didn't convert my boot volume to APFS – it was still Mac OS Extended (HFS+). After converting it to APFS (which was quite tricky) and re-installing High Sierra, I was finally able to install the supplemental update.
I need to boot in recovery mode and recover from the ApFS snapshot that i imagine was created by update process just before instal..
My MBP seems bricked too after the update. Won't boot, end into "MacOS could not be installed on your computer" error.
Then either something went wrong with the update or your machine had a hardware failure during the update process.
You will likely need to use Recovery to restore your Mac.
Error with this update.
