Code review comment for lp:~paride/auto-upgrade-testing-specifications/set-debian-frontend

I'm confused by your latest sentence in the commit message:

"We're not setting DEBIAN_FRONTEND=noninteractive during the upgrade
process, which ideally we don't want to be blocked by debconf."

If we did not want the upgrade process blocked wouldn't we set the frontend to 'noninteractive'. We do want the upgrade to stop if there are debconf prompts so that is why it isn't set. Or am I misunderstanding?