As you are probably aware ConcurrentLicenseManager was discontinued in version 2020 R2. The functionality can, however, fairly easily be mimicked by making your own event server plugin that keeps count of number of current instances and compares that towards the MIP license channel count. Communication with the event server plugin can be done using MIP message communication. We apologize for the extra work needed doing this, but due to security issues with the old solution we had to break compatibility anyways and since it is just a special case of normal licensing we decided to no longer include dedicated functionality for it.