HeatShield's WordPress Firewall is licensed per-site and costs $10/month for each WordPress site. Your first month's charges are prorated through the end of the current month. After that, automatic monthly billing is done on the first day of each month.
HeatShield's WordPress brute force login protection is free and can by used on any number of sites.
If you need WordPress brute force login protection on all of your sites but only need the WordPress Firewall on some of your sites, you can choose to upgrade only some of your sites to the WordPress Firewall.
We do not continue billing you for unused licenses.
If you've deleted a site or downgraded a site to only using the free WordPress brute force protection, your previously purchased license remains available through the end of the period you've paid for (usually the end of the current month). If that license is still unused at the end of its paid period, we'll automatically delete the unused license rather than charge you to renew it.
You can reuse WordPress licenses you've already paid for.
When you downgrade or delete a site, that site's WordPress Firewall license becomes available and will automatically be used the next time you upgrade a site. You'll only be charged when upgrading a site if you don't have any unused licenses available.