I'd give them notice. I'm sorry but I would.
It's a group care situation and after 6 weeks if she's not adjusting, she's unlikely too. I know each province is different but here we can't have anything that can't be sanitized every use and bedding has to be laundered at least every two days. The bed full of toys, blankies, soothers are a thing of the past in a pandemic. Children who are part time struggle to adjust because they are in a constant state of change. Home to day care, day care to home, no wonder so many kids have anxiety these days with no routine. They have no idea what to expect each morning when it switches endlessly.
But at the end of the day, I have a responsibility to all my children and when one child is taking the majority of my time and effects that's unfair. It's to be expected initially but it the transition isn't progressing, it's time to go.