Hi there,
You should be able to login again, and this issue shouldn’t repeat itself. Jetpack’s Protect function looks at the incoming IP address when you try to login, and compares it against our network of blocked IPs. This works pretty well, unless Jetpack’s Protect function is being told the wrong IP address by your site’s server. In your case, your server was reporting its own IP address to Protect, which is why it was blocked. This meant that every single time someone with a WordPress site on your site’s server entered the wrong password, we thought it was the same person. If your hosting provider has several hundred WordPress sites on the same server/IP, that adds up fast, leading to a ban on the IP.
I’ve made a couple of changes on our side, and Jetpack’s Protect feature will now determine incoming IP addresses in a different way. You should be able to enable the protect module again and now be set.
Please let us know if you encounter any login issues, or if we can help with anything else!