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Have I Been Pwned owner, pwned.
(htxt.co.za)
This is a most excellent place for technology news and articles.
Most companies add an email header like "X-PHISHTEST" to the phishing tests (and a corresponding spam filter rule) to ensure they don't get caught by spam filters. If you look at the headers of a spam email, the company test emails will have that header.
Any company that does that needs to be sent on a mandatory awareness training for failing an obvious fake phishing exercise. It's far too easy to whitelist that and send it to an "ignore" folder.