Do i have to change the date of the boarding if a dog gets picked up early but the owner says not to worry about it?

I had a client pick up her dogs around 10PM, but she wasn't supposed to come till about 9AM the next morning. I told her I could change the amount of nights of the booking, but she said not to worry about it. Is it okay if I keep the boarding as is & active, even though the dogs have already left?