Happy Friday!
I am making one bath of cupcakes that are made with sour cream and another batch with frosting that includes sour cream for a party that starts at 5pm tomorrow. I'm assuming I need to keep them refrigerated until then due to the sour cream?

The frosting yes...As for the cake, Im not real sure, I dont mine and they are fine, but I always refrigerate the frosting with cream cheese or sour cream. ( to the best of my knowledge)

This is a great question. Hopefully you get the right answers Ill keep my eyes open.