[MayeulC]

It's true, I assumed there would be multiple targets, maybe that was misguided?

You probably can't use a single website to send those 20 messages (if it's well-designed with a cool down), as the recipient address is the same. So you need 20 different websites to send these.

What outgoing spam rate is acceptable, assuming you can't reach zero? 1 per 10 sec?