The billing cycle anchor setting in your app determines the date of all users' subscription renewals and defines whether the subscription elements' proration for the first subscription period applies.
Set billing cycle anchor
Go to the Locations > Settings > Billing page.
In the "Billing Cycle Anchor" field, select one of the two values:
Subscription Start Date
First Day of the Month
A subscription inherits a billing cycle anchor at the moment of creation. If you change the billing cycle anchor, it will apply only to future subscriptions, but the existing ones will continue to renew according to their current billing cycle anchor.
Subscription Start Date
If "Subscription Start Date" is selected as the billing cycle anchor, users' subscriptions renew and users are billed on the date when they subscribed.
Thus, the first subscription period is not prorated, and users get the first invoice with the full price as well as the full number of credits and day passes.
First Day of the Month
If "First Day of the Month" is selected as the billing cycle anchor, the users' subscriptions renew and users are billed on the first day of each month, regardless of the date when they subscribed.
Thus, if the user subscribes on a date other than the first date of the month, their first subscription period is incomplete. The user receives a prorated invoice and a prorated number of credits and day passes for their first subscription period. The subscription renews on the first day of the month in all subsequent subscription periods with the full invoice price and credits and day pass numbers. Understand how proration works