There are more GRUB list entries now, mostly duplicate. 2 EOS linux-zen, 2 EOS advanced sub-menu, etc., and the same for the other Linux distri.
I tried six different EOS GRUB entries: 2 x linux-zen, 1 x linux, 2 x fallback initramfs, 1 x linux recovery.
None of the six boot options worked. Every six failed on the exact same step as on the fateful Saturday.
I took photos of GRUB menu and can provide them later.