I dont have a helper. But on my POV for morning/afternoon routine I would have helper handle while night routine would be me/spouse. Reason being is we can both take turns to change diaper, pump milk, feeding baby. If you let your helper handle baby at night. Chances of her not doing her task properly in the morning/afternoon would affect her work. She still need to do house chores and handle your baby most of the time. You can get rest in the afternoon and if your spouse does too. Also if you give your helper rest for two hours, what are the chances she would rest ? Would her rest be disturb?
And since your nanny leaves next week, take the chance to know your baby routine and handle it on your own with your spouse. If anything you are unsure, nanny would be around to help.
itsallabout_mytwokids