cnMaestro X is an account-level program, not a device-level program, although the license scheme is based on the number of devices in the account. You only get access to cnMaestro X features when you have licenses for all the devices in the account (excluding free tier devices such as subscriber modules).
For cnMaestro On-Premises, you may have multiple server instances connected to an Anchor account. The licenses are stored in the Anchor account, and for each server instance you can choose whether or not to let it use licenses from the Anchor account.
Please also note that SAML Authentication for cnMaestro Cloud does not require cnMaestro X.