I did not receive all of the errors in the original report, but did receive some of them. This one (and related ones) were most prominent:
/bin/bash: error while loading shared libraries: libdl.so.2: cannot open
shared object file: No such file or directory
Anyway, it seemed to be fixed by forcing an upgrade of initrd-tools from 0.1.81.1 to 0.1.84.1 and modutils 2.4.26-1.2 to 2.4.27-0.5. It could be only one of them; I forced both upgrades at once.