1) How did they hit stable then? [0]

2) Yes, emails absolutely need IRB sign-off too. If you email a bunch of people asking for their health info or doing a survey, the IRB would smack you for unapproved human research without consent. Consent was obviously not given here.

[0] https://lore.kernel.org/linux-nfs/CADVatmNgU7t-Co84tSS6VW=3N...