We are investigating automated email delivery from a paid Google Workspace account that previously used a trial. We need guidance on the distinction between Apps Script recipient quotas and restrictions on external delivery.
Observed evidence:
- The latest verified external MailApp delivery failures were asynchronous DSNs on 13 September 2026:
5.7.1 Message rejected. - An Apps Script diagnostic on 17 September showed remaining daily recipient quota. That does not prove deliverability.
- Two explicitly authorized, low-volume tests through authenticated Gmail SMTP on 17 September were received internally and at an external Microsoft mailbox. Google Email Log Search also confirmed delivery to Microsoft’s server with TLS.
- A separate 16 September attempt failed with HTTP 404 before sending, so it is not evidence about the current MailApp delivery restriction. We have not established a current MailApp success or failure on 17 September.
- Earlier Workspace support associated the failures with temporary trial-to-paid restrictions. A private support case is active and we have requested Workspace developer support for account-side investigation.
Questions:
- Is there official documentation distinguishing an external-delivery restriction on MailApp from the published Apps Script quota increase criteria (payment threshold and waiting period)?
- Which support team can inspect the restriction and provide a verifiable release condition or corrective action?
- Is there a known Apps Script incident matching this combination of evidence that we should link to the private support case?
We are not claiming a general platform bug, and we are not seeking to evade anti-abuse controls. Routine alerts remain paused. We can provide timestamps and full DSNs privately to Google support; we have omitted account identifiers and private support records here.