I am so blunt and "unforgiving" that I would literally walk to the front door, unlock it, open it and say
"You were notified of the change in entrances. This is the last time I am going to address this change. Unless you use the new entrance, I will not accept your child into care. Thank you! See you at the DAYCARE DOOR!" and then I would close the door and lock it behind me.
I am over parents playing stupid, ignorant or oblivious to things they are perfectly capable of understanding.
I don't "play" well with those types of adults so I would handle this much differently than most. I save what patience I have for the kids.
