I can confirm this issue, i had it today, which caused a ~8 Hour Downtime on one of my nodes.
Service started downloading, seems to have stoppend the main node-service, then failed, got restarted by systemd, but the main node-service was not, because the updater-service failed.
No Idea what caused it though.
I changed unitfiles of both services to restart = always as a workaround.