Transport Block containing URLLC and eMBB data

How does a Transport block (TB) containing both URLLC and eMBB data is handled?

Suppose we have a ongoing eMBB data flow going which is coded in such a way that maximum data can be sent but suddenly a URLLC data comes which needs to be coded in different rate to ensure reliability. How does a Transport Block containing both types of data is handled in 5G or gNB

Thanks and Regards,
Pratik Sharma