Custody and Visitation Issues: What if No Custodial Parent Available to Receive Child After Non-Custodial Visitation

My question involves a child custody case from the State of: Arizona. I am the non-custodial parent and I have visitation rights for the Christmas holiday, not to include New Year's. After visitation I am required to take the kids to their father's home, a 5hr drive and 1 state away. The kids' father has told me no adult will be there on the appointed date of custody transfer and asked if I could fly the kids to another state for him or drop them at the airport for him to get them to the state in which he is spending his holiday. What are my responsibilities if there is no adult available to receive the kids, ages 12 and 14, in their father's city of residence?

Custody and Visitation Issues: What if No Custodial Parent Available to Receive Child After Non-Custodial Visitation