As I’ve grown older, I’ve realized that I care a lot less about whether I own the device or the ISP. I’ll happily root the fucking thing. What are they going to do, send me to a competitor? I have 3 different networks I can connect from at any moment (including hotspots), so I’m not worried about a minor lapse due to ISP temper tantrums.
I will tell them casually too. I don’t want their support. I pay for internet access, it’s their problem if they try to make my access conditional beyond that.