Recurring donations are charged on the same day the following month that you initiate the first donation by default. For example, if you made your donation on February 20th, your next charge date would be March 20th by default. The good new is that both the donor and the organization can change the charge date at any time.
PayPal recurring donations are charged every month on the same day of the initial donation. PayPal does not allow a donor or an organization to change the charge date.