Interesting. I have been somewhat weary of the "machine learning for everything!" approach that google has taken recently -- i just don't think it's there yet.

Interesting. I have been somewhat weary of the "machine learning for everything!" approach that google has taken recently -- i just don't think it's there yet. I wonder if a learning algorithm on the google side just started deciding outgoing spam and not giving correct feedback. It is very curious that no url works and with url doesn't. That should give straightforward repeatability (if they can simulate as your account). Have you tried sending to different target e-mail addresses during the test? I saw once it just worked and a bunch of stuff flew through. Also saw there was some question as to quotas. Did you get it clarified? Are you maybe above usage quotas with the regular e-mails so test e-mails are being stopped/delayed? Are test and production separate? It seems like if it were a google side issue there would be an uproar from the users.