@Gurbage, you paid for 30 days and you will have access to Members for your 30 days. The re-bill date is a buffer to allow for you to cancel without being re-billed or to fix bank issues on your end, so that you don't lose P2P without an opportunity to fix them.
Please be aware that the 1-month-subscription continues with automatic re-bill, which is why the buffer exists in the first place. If you only want a single month's subscription, you have to cancel, before your next billing date. Please see your Account Page, accessed via a link at the top of the screen, to check this information.
In future, if you have any Payment related questions or concerns, please post a thread in the
Community Led Payment Support
forum.