Email sending to many addresses

Hello,
Is possible to send more than one email (on row add), using email_sending or other server event? how?
Because I have to send the same message to different mail addresses, so I I have to send many messages, not just one.
I can’t use one message with multiple recipients because of a limitation of my smtp server.
Thanks for the attention

You may just change the Recipient property of the Email object and call send() again.

thank you, now I discovered that my smtp server doesn’t allow more than 15 messages in one minute, so I’d like to send a multi-recipient message (15 recipients) and another multi-recipient message after 1 minute, but if I use sleep() in row_inserted or email_sending events I stuck the return to the list page for one minute. Is there a way to avoid this? I’d like to posticipate the second sending, but I also want the return to the list page just after the inserting (add)

PHP is not asynchronous, you cannot return before the script is executed.