73-seat-late.rules is provided by elogind
I see the same error in /var/log/messages - the offending line is TAG=="uaccess", ENV{MAJOR}!="", RUN{program}+="/usr/local/lib/elogind/elogind-uaccess-command %N $env{ID_SEAT}"
I'd guess that either "RUN{Program}" is depreciated or the dbus/elogind daemon was not running when the rule was loaded?