The hours worked can come into it in determining if there has been a "substantial loss of employment"
So if your employer changed you from 5 x 7 hour days, to 3 x 12 hours, then you haven't suffered a loss of employment even though you are now only working 3 days a week.
My employer changed me from working seven 12 hour shifts in two weeks (84hours of which 78 hours were my contracted hours and the remaining six hours were overtime) to the above.