I agree with Playfelt. I would ask for a schedule by Friday close for the following week. Anyone who can't plan like that while on mat leave (I'm assuming on mat leave) is not someone I want in my care. I would need to know numbers for meal planning and craft planning anyways.

If she's just by email right now then you can really send this message from day one. Good for you for looking for answers before you need them. Great job being prepared.