Next due date start count when product is Active

Hello,

I would like my products billing to be calculated as soon as they are Active, not as soon as they are ordered.

For example, my customer orders a hosting plan. For figure of speech I activate it one week later, the client will still be billed for those 7 days, even though his order was "Pending".

I would like the billing to be counted as soon as the product is "Active".

Any suggestions?
Thanks!