Comment 1 for bug 1913087

I've had this very experience just last week. Beyond /target (and many things under it) being mounted there is some persistent state between subiquity restarts (which is nice for the auto-update path) however it may be causing issues when some selections changes. For example, I played with setting/removing proxy and setting/removing mirror; the result after a few failures was subiquity writing an apt file in the /target/etc/apt overlay mount which apt could not parse (it had errors).

There should be a way to clear out this persistent setting surfaced to the user on restart after crash (do you want to keep your previous choices?)