Weekly subscription product - When is the client billed?

Hi,

Here is something I have not been able to find instructions for, or posts about. I am a bit frustrated with the very "light" instructions provided by Squarespace concerning subscription products.

1. If I provide weekly subscription products to my clients via local delivery, when exactly will my clients be billed? 
2. Will they be billed on a specific day of the week, or every 7 days after they subscribed? 
3. Or are they going to be billed manually every time I fulfill their weekly orders? 

Furthermore, If I have to delay a weekly subscription renewal, how much time in advance do I need to enter the delay in the Squarespace's platform in order to make the weekly billing cutoff and skip that week's billing? 

Thanks in advance for your guidance.