Well she needs to arrive ready to participate so I would go in with that angle. She is clearly over tired in the mornings and it is effecting her behaviour at daycare. I would ask them how she is sleeping and what time she goes to bed at night. It is possible that having different bedrooms and expectations are impacting her ability to sleep even if she is going down at the same time at both houses. An email addressed to both of them is how I handle divorcing couples as they both feel included and they both then know the concerns.