Our subscription payments are processed by Braintree - a division of PayPal. The $1 amount that may appear on your bank balance is what's known as a pre-authorisation charge. It is used to ensure that card is valid, is not stolen and has sufficient funds. The following is taken from Braintree's support documentation. If you would like any further clarification please contact us at firstname.lastname@example.org
"The Braintree gateway verifies credit cards by running either a $0 or $1 authorization and then automatically voiding it. For most processors, Visa and Mastercard are initially tried with $0 authorizations. Some card types, such as American Express and Discover, don't consistently support $0 authorizations. These cards must instead be verified with $1 requests. In any instance where a $1 authorization returns a successful result, we immediately follow up with an automatic void request to ensure that the transaction does not settle and that it disappears from the cardholder's statement as soon as possible."