Subscription Duration
When you receive your Parallels Desktop Business Edition license key, your subscription becomes effective immediately. When you activate Parallels Desktop on a Mac computer using the license key that came with your subscription, it will stay active for the duration of the subscription.
You should renew your subscription in advance of the expiration date to avoid any unintended service interruption. If you miss the expiration date and don't renew your subscription, Parallels Desktop will stop working on your users' computers.