All accruals/withdrawals of bonus points, whether it’s a regular accrual or a promotion organized in the Auto Actions section, are a very resource-intensive process in terms of technical resources.
Therefore, all accruals work ONCE PER HOUR, every hour at XX.00 the plugin checks all campaigns and perform operations.

Including e-mails notifying about accrual are sent once an hour. And in the settings -> main you can set how many emails to send at a time per hour, so as not to overload the system.

Emails to send per session. This option is required to control the number of emails sent, promotions, and automatic actions. All scheduled emails are sent once per hour. Determine how many emails to send at one time. (Default value = 30 emails per hour)

Check out our documentation to learn more about other WupSales Reward Points for Woocommerce options.
Also, if you have any questions, please contact us and we will be happy to help you.