What is the calmest way to triage an ads.txt warning?

A practical ads.txt troubleshooting question for creators and small publishers.

ads.txt warnings can trigger a lot of unnecessary edits. My calm checklist is public URL, exact publisher line, www vs non-www, redirect behavior, cache, and whether the warning is separate from a normal revenue swing. Repeatedly changing the file before proving what is live seems risky. For small publishers, what is the shortest ads.txt triage that catches real mistakes without overreacting to a delayed recheck?