In you case the most important setting is “Maximum number of emails that can be sent in a 24-hr period”. If you have to send max 500 emails per hour (let’s say 480; keep 20 for registrations, password recoveries…), make this count:
480 emails * 24 hours = 11520 emails-per-day
so put 11520 in “Maximum number of emails that can be sent in a 24-hr period”.
I suggest that you leave “Maximum number of emails that can be sent per batch” equal or less than 30 (even if you can send untill 40 emails per batch: 480 emails / 12 batches-per-hour = 40 emails-every-5-minutes), and “Interval between emails in a single batch” equal to 0.
I too have a 500 email per hour limit sending out emails. I have had some issues with the newsletter plugin internal cron, and wasn’t sure if throttling was working correctly. And my host company disables wget (and get) since I am on a shared server.
I have been testing this in my cPanel and it seems to be working:
curl –No-output http://www.MySite.com/index.php (be sure the “N” is capitalized)
“curl” calls the URL (i.e.; curl) and sends the request to a standard output stream (aka: stdout). And by adding the “–No-output” option (without the quotes) in front of the URL will prevent an output stream from being generated.
In setting up your cron job (assuming your host gives you that capability), then you can schedule the above command to whatever you want. For testing I set it at five minutes, and I could see it was calling the page. So, when I get other issues worked out, I will set my schedule to once ever hour, with the hope that throttling my emails will be more precise.
I suspect, and hope, that by calling WordPress index.php file, WordPress will recognize it as an actual hit.
