On 19/12/2019 09:46, Peter J. Holzer wrote:
I vaguely remember that there was a draft for an extension where the
server could communicate a hold time to the client. Something like "try
again in 5 seconds" for too many recpients or "try again in 24 hours"
for a full mailbox.
There was https://tools.ietf.org/html/draft-santos-smtpgrey-02
but I don't think it gained traction.
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