Payment will be charged to your iTunes account at confirmation of purchase.
Subscription automatically renews unless auto-renew is turned off at least 24-hours before the end of the current period.
Your account will be charged for renewal within 24-hours prior to the end of the current period.
To manage subscriptions or turn off auto-renewal go to your iTunes account settings after the purchase.
Any unused portion of the free trial period will be forfeited when you purchase a subscription.