The 'relevant authority' (the employer) is obliged to decide what amount of incapacity is payable to the employee where he or she is undertaking a part-time program only.

Understandably, this paragraph is rare, but does ensure that the employee, undertaking part-time rehabilitation only, is not paid any more than he or she would if undertaking a full-time program.  Concurrently, the paragraph also ensures that the employee is not paid any less than he or she would if section 19 or 31 applied.