@GrapheneOS, since ive installed the latest version of DNSnet, I haven't received any device software update at all. One day I've checked my Info app to see where I was and Ive missed quite a few updates maybe about a month full.
After stopping the service AND the option "reenable after reboot", + reboot of the device, it's installing an update now.
I'm thinking that some of my hosts lists (or the whole app) is blocking GrapheneOS System Updater in some ways.
Here's my DNSNet config (I think I've added 1-2 host files lists as you can see):