@alice I do expect they can do anything they like 'cause no matter who I paid what, it isn't MY phone, but my griping aside, what I want to block are System updates; they give me an option to _delay_, but I want similar to Linux where I can simply stop checking for updates.

Which brings up #GrapheneOS; it is said run on my Samsung S20, but (a) it is a one way trip and (b) I am not yet completely off my Google Workspace that also includes family members (all reluctant to change), so I would still be tied to Google and not sure how Graphene sits in that situation. As much as I try to use FDroid apps, there are still many I can only get via Google although perhaps there will be a Reform Movement in the pirate apk shops, trojan-free like it used to be.