What does the log message no immediate delivery: more than 10 messages received in one connection mean?

A remote MTA sent a number of messages in a single SMTP session. Exim limits the number of immediate delivery processes it creates as a result of a single SMTP connection, in order to avoid creating a zillion processes on systems that can have many incoming connections. If you are dialing in to collect mail from your ISP, you should probably set smtp_accept_queue_per_connection to some number larger than 10, or arrange to start a queue runner for local delivery (using -ql) immediately after collecting the mail.

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