When does Zoho Subscription auto charge when card is on account and new invoice

When does Zoho Subscription auto charge when card is on account and new invoice

Hi,
I have a questions when does zoho subscriptions charge a card for a newly created invoice.
I have a customer + sub that they paid for.  Several days later they want to upgrade to a higher priced subscription. We update their subscription ( via API) then Zoho creates the new invoice ( prorated for the days till renewal) and creates a credit memo and applies it to the newly created invoice, leaving the invoice open with the prorated amount due. This is beautiful.

However, When will the customers card be charged for the open invoice? Do we have to manually collect this or will Zoho.Sub take notice of this and charge the card like at the top of the hour?

Can we tell Zoho.Sub to also charge the card for the prorated amount when it does all the other stuff??