next googler who emails me will get an bill for my time in fixing this. i've added you to my invoicing system google.
hmm, my IPv6 PTR record already was set correctly. google's bounce links to https://support.google.com/mail/?p=IPv6AuthError .. which fails to mention PTR records and tries to get you hooked on some Google Postmaster Tools BS
guess I'm billing google 1 hour for inconclusive investigation?
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