It appeas that systemctl was replaced with synoservicectl after DSM 6.1 and when I run:
sudo synoservicectl --stop hassio-supervisor.service
as per Uninstall hassio , I get hassio.supervisor.service failed to stop…error unknown [0x400 servicectl_status.c:27]. Has anyone dealt with any of this? It’s getting ridiculous and I’m about to buy a darn Hubitat C7