Services in Thoradia Add-ons all use system.d
Radarr is defined in /storage/.kodi/addons/service.radarr/system.d/service.radarr.service
Replace radarr by sonarr, bazarr, jackett for the others
These files are reset whenever the add-on is updated
No need to restart them
I accessed here. The structure looks a lot like systemd.
I talk about restart because after the upgrade to new version of LibreELEC and install bazarr in my system (raspberry pi) they freeze after some hours running.
All this apps (sonarr, radarr, bazarr and jackett) allocated a lot of ram memory and don't release they. I desactivate bazarr and will see if the freeze persist.
Before the upgrade for beta version I used a old version of sonarr and radarr, because it was the available in thoradia and the system don't freeze. Maybe this (the new versions of apps) afftect the system too.