As per the current By-Laws:

3.1.1 Eligibility (AHT) Clinician 

10. Maternity leave:  Allowance for clinical hours with an extension of up to 1 year per child with written proof of leave may be granted on request. 

The maternity leave provisions relate to clinical hours only. 

ie. The 3600 clinical hours could be worked over 6 years (rather than 5), if an extension was sought, but the courses (and the mentorship) would have to have been completed within the 5 years preceding the application.