Parent always late!!!

So I’ve been working with this family for about a year and a half now. The parents are divorced so the weeks are split between the Mom and dad’s houses. The mom is super punctual and always texts when she’s going to be a few minutes late. However, the dad will ask me to work late saying he’ll be home at 9:30 and every time he’s done this he has been an hour + late....I am super peeved that he continues to do this and just thinks I can watch the kids forever?! I already nanny them 5 days a week, and I’m feeling used. Any tips on how to address the dad?