The serial number is universal (compatible with all supported Creative Cloud versions that we offer) and works for all coming releases of Creative Cloud, currently, we only support macOS. By subscribing, you never need to concern yourself with changing your serial number, you will be able to stick to the same license at all times as long as you subscribe. Please note that this is a yearly auto-renewal billing plan (subscription). If you ever wish to unsubscribe you can do so via the link that you will get in any of your receipt(s) after payment(s). In the link, you can see your next billing date and also change your payment details. Please note that we only offer volume pricing on yearly subscriptions. When subscribing on a yearly plan you will get a notification before next billing is made. We do not offer refunds on subscription fees, by placing your order you agree to this.