ITA 
Employer can change the working time to full-time employees
The limits on the right to modify working hours provided for part-timers do not apply to full-time employees. In such a case, the right may be limited only by agreements.
Court of Cassation, Order No. 31349 of 03 November 2021.
Protected period on case of illness: it is presumed the continuity of the illness even in vertical part-time work
Also in the vertical part-time employment relationship it must be taken into account, for the purpose of calculating the illness protected period (i.e. the period of absence from work, for illness or injury, during which the employee cannot be dismissed), the non-working days falling in the period of absence, assuming the continuity of the illness.
Tribunal of Rome, order of July 18, 2021