Ah ok, right you are. Well the way it works is that it runs apt with only the /etc/apt/sources.list.d/security.sources.list enabled. So if you comment out the Debian repos in that file (or just remove the lines), that should achieve what you are after.
You'll likely want to put those Debian security repo lines into another file. Either add them to /etc/apt/sources.list.d/sources.list (just add them on the bottom) or put them in their own file (just a text file, with a '.list' file extension). If you don't include those lines somewhere else, when you run apt, you won't be getting packages from the Debian security repo. That may or may not be an issue with your patching system, but I thought it worth mentioning.
Ah ok.
Ah ok, right you are. Well the way it works is that it runs apt with only the /etc/apt/sources.list.d/security.sources.list enabled. So if you comment out the Debian repos in that file (or just remove the lines), that should achieve what you are after.
You'll likely want to put those Debian security repo lines into another file. Either add them to /etc/apt/sources.list.d/sources.list (just add them on the bottom) or put them in their own file (just a text file, with a '.list' file extension). If you don't include those lines somewhere else, when you run apt, you won't be getting packages from the Debian security repo. That may or may not be an issue with your patching system, but I thought it worth mentioning.