I usually move to Lineage once my two year warranty is up, just in case.

I know that by law hardware manufacturers can’t deny hardware warranty based on your software (at least where I’m from…I worked in for one of the big three telco’s up here in Canada)

But I’d rather not have that argument with the manufacturer, so I wait for it to run out. If my phone has a rom available I run that until the hardware dies and then I upgrade.