If you want to give some time to the parents to find alternative care maybe you could terminate and make it effective in 2 weeks or whatever you feel comfortable with. If they find care at the end of the 2 weeks and she starts to be happy while in your daycare and you want her to stay I do not think parents would want to send her with someone else and start transitioning again. If they find daycare anytime within the 2 weeks it will be good for you and for the family.