It appears that App Engine is not always sending email. This may be the case with both probe emails and failed probe notifications.
Failed probe emails could be the cause of #1.
Failed probes are clearly being set to a status of 0 (failed), but for the number that I'm seeing, most aren't accompanied by a notification email.
Some first steps could include better logging and error handling.
Also wondering if some email quotas are being hit.
It appears that App Engine is not always sending email. This may be the case with both probe emails and failed probe notifications.
Failed probe emails could be the cause of #1.
Failed probes are clearly being set to a status of 0 (failed), but for the number that I'm seeing, most aren't accompanied by a notification email.
Some first steps could include better logging and error handling.
Also wondering if some email quotas are being hit.