Automatic Refresh: This option will replace all your proxies periodically, so you don't have to worry about it.

On-demand Refresh: If you prefer more control, you can replace all your proxies whenever possible. If your subscription has two on-demand refreshes, you can replace all your proxies twice a month.

Replacements: You can also replace proxies individually. With 500 proxy replacements, you can replace 500 proxies every month.