Hello @Tom Austin ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
I understand that you have Azure Front Door Premium SKU domains with AFD Managed certificates and you would like to know the auto-rotation timeline for same.
As per this documentation - For the Azure Front Door Standard/Premium managed certificate option, the certificates are managed and auto-rotates within 45 days of expiry time by Azure Front Door. If you are using a Front Door managed certificate and see that the certificate expiry date is less than 30 days away, file a support ticket.
From the screenshot provided by you, it looks like you still have 9 days period for the certificate auto-rotation to happen, as it says 'Expiring in 39 days'. You can wait for 9 more days and if the expiry date goes less than 30 days, only then you would need to file a support ticket.
Kindly let us know if the above helps or you need further assistance on this issue.
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