No.
Although the license works in a WordPress multi site environment, your Lifetime Brizy PRO license can't be used to create a WaaS business.
For a WaaS business model you need to get a WaaS license from us.
If you own a Lifetime Brizy PRO license and want to upgrade to a WaaS license, you can pay the difference and upgrade to a WaaS license but lose access to the Lifetime license in the process.
If you decide to keep both, we can offer you a 30% discount on the WaaS license.
Contact us on hello@brizy.io so we can help you with the upgrade.