When am I charged for a creator subscription?
Creators/Promotional account can have optional paid memberships to some areas of their profiles. All paid subscriptions to content creators are billed upfront on the day you become a supporter. The billing is monthly and automatically renewed on the 1st of each month. The reason you are billed immediately is because you get access to all of the creator's past and future posts including any live videos.
For example, if you choose to become a supporter of a creator on May 25th and the creator's price is $9.99 a month, you will be charged $9.99 immediately for May and then on June 1st for June and every month after.