Here is some informations based on the documentation.
The Co-Termination model works on the basis of co-termination, which means that for any given organization, regardless of how many licenses were applied or when they were applied, the license expiration date for all licenses claimed to that organization will be exactly the same. This is accomplished by averaging all active licenses together and dividing by the license limit count of devices in the organization.
The Per Device Licensing model allows customers to assign a license directly to a specific device or a network. This allows IT teams to maintain a single shared expiration date or various expiration dates across devices, networks, or organizations.
Both models are options available to Meraki customers, and the choice between them depends on the customer’s unique business needs. It’s important to note that once a customer chooses the Per Device Licensing model, they cannot change back to the Co-Termination model.
Meraki Licensing - Cisco Meraki Documentation
Meraki Licensing FAQs - Cisco Meraki Documentation
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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