It is not possible to accept or confirm more students to a course than the number of students set at the time of the course creation. This number depends on the number of training rigs that have been approved for your training centre. Should you want to increase the number of students for a particular course type, then the training centre has to update its training centre profile thereby adding additional training rigs. How to update the training centre profile is explained here.
Example: Max. 10 students can be confirmed to a course:
