Yamadera and Zao day-trip from Sendai

Hello, I'm planning to travel to Yamadera and Zao in a day trip via JR and buses, leaving from and returning to Sendai. It will be either December 17/18th. I'm wondering how crowded the Zao ropeway would be in days before skiing is open, since I'm planning to go to Yamadera first and I want to plan how early I should depart in the morning. Thank you!!

I don�ft know about the crowds, but be aware of sunset. You will want to be down back in Zao onsen well before that.
So I�fd start as early as possible in the morning.

(Frankly I�fd do it from Yamagata but I do understand that changing hotel is a added complication)