lb binary fails on line 72

[Borden <borden_c@tutanota.com>]

I'm trying to build an image using live-build 20210216. It's getting towards the end and fails suddenly with error message

find: ‘binary’: No such file or directory
E: An unexpected failure occurred, exiting...

I think I've traced the offending code to line 72 of /usr/lib/live/build/binary:
# Apply SOURCE_DATE_EPOCH to all modified and created files
find binary -newermt "$(date -d@${SOURCE_DATE_EPOCH} '+%Y-%m-%d %H:%M:%S')" -printf "%y %p\n" -exec touch '{}' -d@${SOURCE_DATE_EPOCH} --no-dereference ';' > binary.modified_timestamps

Is this a known problem and, if so, what's the workaround?