amp-email: no reply/progress to Sender registration since 29 july

## Description
Hoping someone can please help! Canva submitted a formal AMP Email sender registration request on 29 July 2026, resent our AMP email, and resubmitted the form on 31 August. However, we haven't received an automated confirmation, rejection notice, or follow-up regarding our allowlist status.

We are opening this tracking issue to request an engineering status lookup.

## Context
- **Email address your AMP emails will be sent from:** marketing@engage.canva.com
- **Submission Date:** 29 July 2026 and 31 August 2026
- **Company website:** https://www.canva.com/

## Technical Verification
- **Authentication:** SPF, DKIM, and DMARC are fully aligned, active, and strictly passing.
- **Postmaster Tools:** Google Postmaster Tools reports 0 validation errors and a healthy domain reputation.
- **MIME Format:** Validated successfully via the AMP for Email Playground. No forwarding was used.

The payload names no repository file, test, or entry point. Start by reviewing the AMP Email sender-registration workflow and the two submission dates; done means confirming the allowlist status or providing the missing confirmation, rejection, or follow-up.

Written by the indexing model from the issue text.