As per my knowledge, everything is dynamic assignment.
You can control and setup user or login access rules to assign the licenses as required.
Review the help information for more details
We don't have the CAL's concept as is in QlikSense, we may use the Access Passes instead .
In Qilk Sense you have the concept of a token to manage access and this can be used in a number of ways as you see fit.
1. As a login access for a named user any time and with potentially full permissions dependent on how you set up security rules.
2. A session access which allows any user up to 10 hours every 28 days
3. An analyser token for a named user to access at any time but read only (new)
The idea of the concurrent access is not currently supported.
Hope this helps