I just want to report that we are suffering from this bug, and it is quite frequent. This is with version 215-17+deb8u5 .
root@a12:~# systemctl status systemd-journald *** systemd-journald.service - Journal Service Loaded: loaded (/lib/systemd/system/systemd-journald.service; static) Active: *failed* (Result: start-limit) since Sat 2016-10-15 12:01:57 EDT; 8h ago Docs: man:systemd-journald.service(8) man:journald.conf(5) Process: 51561 ExecStart=/lib/systemd/systemd-journald *(code=killed, signal=USR1)* Main PID: 51561 (code=killed, signal=USR1)